Investment Grade Corporate Trust, 3-7 Year Series 34

Investment Grade Corporate Trust, 3-7 Year Series 34 invests in a portfolio of investment grade corporatebonds, generally maturing approximately 3 to 7 years from the Date of Deposit. The Trust seeks to provide ahigh level of current income and to preserve capital. The Trust is a unit investment trust included in InvescoUnit Trusts, Taxable Income Series 637.

Monthly Distributions _____________ Estimated Current Return: 3.10%

Estimated Long Term Return: 0.98%

Estimated current return shows the estimated cash you should receive each year divided by the Unit price.Estimated long term return shows the estimated return over the estimated life of your Trust. We base thisestimate on an average of the bond yields over their estimated life. This estimate also reflects the sales chargeand estimated expenses. We derive the average yield for your portfolio by weighting each bond’s yield by itsvalue and estimated life. Unlike estimated current return, estimated long term return accounts for maturities,discounts and premiums of the bonds. These estimates show a comparison rather than a prediction ofreturns. No return calculation can predict your actual return. These estimates are as of the opening ofbusiness on the Date of Deposit and will vary thereafter. Your actual return may vary from these estimates.

October 7, 2021

You should read this prospectus and retain it for future reference.

The Securities and Exchange Commission has not approved or disapproved of the TrustUnits or passed upon the adequacy or accuracy of this prospectus.

Any contrary representation is a criminal offense.

INVESCO

Investment Objective. The Trust seeks to providea high level of current income and to preserve capital.

Principal Investment Strategy. The Trust investsin a portfolio of investment grade corporate bondsmaturing approximately 3 to 7 years from the Date ofDeposit. In selecting bonds for the Trust, the Sponsorconsidered the following factors, among others:

• all ratings provided for the bonds must be atleast “BBB-” if issued by either Standard &Poor’s or Fitch Ratings, and at least “Baa3” ifissued by Moody’s Investors Service, Inc. or,in the case of a bond with no issued ratings,such a bond has credit characterist icssufficiently similar to those of comparablebonds that were so rated as to be acceptablefor acquisition by the Trust in the opinion ofthe Sponsor;

• the prices of the bonds relative to otherbonds of comparable quality and maturity;

• the current income provided by the bonds;

• the diversification of bonds as to purpose ofissue and location of issuer; and

• the probability of early return of principal orhigh legal or event risk.

The portfolio generally consists of taxable bondsmaturing approximately 3 to 7 years from the Date ofDeposit. Following the Date of Deposit, a bond maycease to be rated or its rating may be reduced, even tobelow “investment grade” (“BBB-” or “Baa3”), and theTrust could continue to hold such bond. See “TrustAdministration--Portfolio Administration”.

Principal Risks. As with all investments, you canlose money by investing in the Trust. The Trust alsomight not perform as well as you expect. This canhappen for reasons such as these:

• Bond prices will fluctuate. The value ofyour investment may fall over time.

• The value of the bonds will generallyfall if interest rates, in general, rise. Ina low interest rate environment r isksassociated with rising rates are heightened.The negative impact on f ixed incomesecurities from any interest rate increasescould be swift and significant. No one canpredict whether interest rates will rise or fall inthe future.

• A bond issuer or insurer may be unableto make interest and/or principalpayments in the future.

• The financial condition of an issuer mayworsen or its credit ratings may drop,resulting in a reduction in the value ofyour Units. This may occur at any point intime, including during the primary offeringperiod.

• During periods of market turbulence,corporate bonds may experienceilliquidity and volatility. During suchperiods, there can be uncertainty in assessingthe financial condition of an issuer. As a result,the ratings of the bonds in the Trust’s portfoliomay not accurately reflect an issuer’s currentfinancial condition, prospects, or the extent ofthe risks associated with investing in suchissuer’s securities.

• A bond issuer might prepay or “call” abond before its stated maturity. If thishappens, the Trust wi l l d istr ibute thepr incipal to you but future interestdistributions will fall. A bond’s call pricecould be less than the price the Trust paidfor the bond.

• The Trust is concentrated in bondsissued by companies in the financialsindustry. Negative developments in thisindustry will affect the value of your investmentmore than would be the case in a morediversified investment.

• Bonds of foreign issuers present risksbeyond those of U.S. issuers. These risksmay include market and political factors relatedto an issuer’s foreign market, international tradeconditions, less regulation, smaller or less liquidmarkets, increased volatil ity, differingaccounting practices and changes in the valueof foreign currencies.

• We do not actively manage the Trust’sportfolio. Except in limited circumstances,the Trust will hold the same bonds even if themarket value declines.

2

3

(1) Some bonds may mature or be called or sold during your Trust’s life. This could include a call or sale at a price below par value. We cannotguarantee that the value of your Units will equal the principal amount of bonds per Unit when you redeem them or when your Trust terminates.

(2) During the initial offering period, part of the value of the Units represents an amount of cash deposited to pay all or a portion of the costs oforganizing the Trust. The estimated organization costs per Unit will be deducted from the assets of the Trust at the earlier of six months after theDate of Deposit or the end of the initial offering period. If Units are redeemed prior to any such reduction, these costs will not be deducted from theredemption proceeds. Organization costs are not included in the Public Offering Price per Unit for purposes of calculating the sales charge.

(3) After the first settlement date ( October 12, 2021 ), you will pay accrued interest from this date to your settlement date less interestdistributions.

(4) This shows estimated expenses in the first year other than organization costs. Organization costs are not deducted from interest income.(5) Your Trust assesses this fee per $1,000 principal amount of bonds. Your Trust assesses other fees per Unit.(6) We base this amount on estimated cash flows per Unit. This amount will vary with changes in expenses, interest rates and maturity, call or

sale of bonds. The Information Supplement includes the estimated cash flows.(7) The Public Offering Price shown above reflects the value of the bonds at the opening of business on the Date of Deposit. No investor will

purchase Units at this price. The price you pay for your Units will be based on their valuation at the Evaluation Time on the date you purchaseyour Units. The initial evaluation for purposes of determining the purchase, sale or redemption price of Units on the Date of Deposit will occurat the latter of the close of regular trading on the New York Stock Exchange or the effectiveness of the Trust. Thereafter, evaluations forpurposes of determining the purchase, sale or redemption price of Units are made as of the close of regular trading on the New York StockExchange on each day on which it is open, or earlier on days where the Bond Market Association recommends an early bond market close(the “Evaluation Time”).

Summary of Essential Financial Information(As of the opening of business on the Date of Deposit)

General InformationDate of Deposit October 7, 2021 Principal amount of bonds in Trust $4,800,000Principal amount of bonds per Unit (1) $1,000.00Number of Units 4,800Weighted average maturity of bonds 5 years

Unit PriceAggregate offering price of bonds in Trust $ 5,274,117Aggregate offering price of bonds per Unit $ 1,098.77

Plus sales charge per Unit $ 21.86Plus organization costs per Unit (2) $ 8.85

Public offering price per Unit (3)(7) $ 1,129.48Redemption price per Unit (2)(3) $ 1,106.33

Portfolio Diversification (% of Par Value)Financials 33%Energy 23Real Estate 12Health Care 9Consumer Staples 7Information Technology 6Consumer Discretionary 5Industrials 4Communications 1 _____Total 100% _____ _____

Estimated Annual Income Per UnitEstimated interest income $ 37.96

Less estimated expenses (4) $ 2.98Estimated net interest income $ 34.98

ExpensesSales Charge (% of Unit Price) 1.95%Organizational Costs per Unit (2) $ 8.85 ___________ ___________

Estimated Annual Expenses per UnitTrustee’s fee (5) $ 0.91Supervisory, bookkeeping and

administrative services fee $ 0.55Evaluation fee (5) $ 0.35Other operating expenses $ 1.17 ___________

Total annual expenses per Unit $ 2.98 ___________ ___________

Estimated DistributionsInitial interest distribution $ 2.72 on November 25, 2021Subsequent interest distributions (6) $ 2.91Record dates 10th day of each monthDistribution dates 25th day of each month

CUSIP NumbersMonthly 46136J-76-9Monthly Fee Based 46136J-77-7

PORTFOLIO (as of the opening of business on the Date of Deposit) Cost ofAggregate Name of Issuer, Title, Interest Rate and Redemption Bonds ToPrincipal Maturity Date of Bonds (1)(2) Ratings (3) Feature (4)(5) Trust (2)___________ ______________________________________________________ ___________________ ________________ ____________ CORPORATE BONDS - 100.00% Communications - 1.25%$ 60,000 Comcast Corporation #3.30% Due 04/01/2027 . . . . . . . . . . . . . . . . . . . . . . . . . A- A3 2027 @ 100 $ 65,672 Consumer Discretionary - 4.51% 220,000 Southwest Airlines Company #3.45% Due 11/16/2027 . . . . . . . . . . . . . . . . . . . . . . . . . BBB Baa1 2027 @ 100 237,677 Consumer Staples - 7.51% 350,000 BAT Capital Corporation 4.70% Due 04/02/2027 . . . . . . . . . . . . . . . . . . . . . . . . . . BBB+ Baa2 2027 @ 100 395,997 Energy - 23.31% 200,000 +BP Capital Markets plc 3.535% Due 11/04/2024 . . . . . . . . . . . . . . . . . . . . . . . . . A- A2 ________ 216,134 210,000 +Enbridge, Inc. #4.25% Due 12/01/2026 . . . . . . . . . . . . . . . . . . . . . . . . . BBB+ Baa1 2026 @ 100 236,239 350,000 +Canadian Natural Resources, Ltd. #3.85% Due 06/01/2027 . . . . . . . . . . . . . . . . . . . . . . . . . BBB- Baa2 2027 @ 100 383,264 350,000 Boardwalk Pipelines LP #4.45% Due 07/15/2027 . . . . . . . . . . . . . . . . . . . . . . . . . BBB- Baa3 2027 @ 100 393,862 Financials - 33.53% 210,000 +Mitsubishi UFJ Financial Group, Inc. #3.85% Due 03/01/2026 . . . . . . . . . . . . . . . . . . . . . . . . . A- A1 ________ 232,134 205,000 +HSBC Holdings plc #4.30% Due 03/08/2026 . . . . . . . . . . . . . . . . . . . . . . . . . A- A3 ________ 227,958 215,000 JPMorgan Chase & Company #3.30% Due 04/01/2026 . . . . . . . . . . . . . . . . . . . . . . . . . A- A2 2026 @ 100 232,675 200,000 Bank of America Corporation #3.50% Due 04/19/2026 . . . . . . . . . . . . . . . . . . . . . . . . . A- A2 ________ 218,152 215,000 +Sumitomo Mitsui Financial Group, Inc. 2.632% Due 07/14/2026 . . . . . . . . . . . . . . . . . . . . . . . . . A- A1 ________ 226,434 150,000 Jefferies Group LLC / Jefferies Group Capital Finance, Inc. #4.85% Due 01/15/2027 . . . . . . . . . . . . . . . . . . . . . . . . . BBB Baa3 ________ 174,083 215,000 +Mizuho Financial Group, Inc. 3.663% Due 02/28/2027 . . . . . . . . . . . . . . . . . . . . . . . . . A- A1 ________ 237,506 200,000 Brighthouse Financial, Inc. 3.70% Due 06/22/2027 . . . . . . . . . . . . . . . . . . . . . . . . . . BBB+ Baa3 2027 @ 100 219,602 Health Care - 8.64% 215,000 +Medtronic Global Holdings S,C,A. 3.35% Due 04/01/2027 . . . . . . . . . . . . . . . . . . . . . . . . . . A A3 2027 @ 100 234,885 200,000 UnitedHealth Group, Inc. #3.375% Due 04/15/2027 . . . . . . . . . . . . . . . . . . . . . . . . A+ A3 ________ 220,854 Industrials - 3.98% 190,000 Trimble, Inc. #4.75% Due 12/01/2024 . . . . . . . . . . . . . . . . . . . . . . . . . BBB- Baa3 2024 @ 100 210,106

4

PORTFOLIO (as of the opening of business on the Date of Deposit) (continued) Cost ofAggregate Name of Issuer, Title, Interest Rate and Redemption Bonds ToPrincipal Maturity Date of Bonds (1)(2) Ratings (3) Feature (4)(5) Trust (2)___________ ______________________________________________________ ___________________ ________________ ____________ Information Technology - 5.93%$ 210,000 +Flex, Ltd. #3.75% Due 02/01/2026 . . . . . . . . . . . . . . . . . . . . . . . . . BBB- Baa3 2026 @ 100 $ 228,161 80,000 Oracle Corporation #2.80% Due 04/01/2027 . . . . . . . . . . . . . . . . . . . . . . . . . BBB+ Baa2 2027 @ 100 84,744 Real Estate - 11.34% 135,000 American Tower Corporation #4.00% Due 06/01/2025 . . . . . . . . . . . . . . . . . . . . . . . . . NR Baa3 2025 @ 100 147,519 220,000 Corporate Office Properties L.P. #2.25% Due 03/15/2026 . . . . . . . . . . . . . . . . . . . . . . . . . BBB- Baa3 2026 @ 100 225,887 200,000 W.P. Carey, Inc. #4.25% Due 10/01/2026 . . . . . . . . . . . . . . . . . . . . . . . . . BBB Baa2 2026 @ 100 224,572___________ ____________$ 4,800,000 $ 5,274,117___________ _______________________ ____________

For an explanation of the footnotes used on this page, see “Notes to Portfolio”.

5

6

Notes to Portfolio

(1) The bonds are represented by “regular way” or “when issued” contracts for the performance of which an irrevocable letterof credit, obtained from an affiliate of the Trustee, has been deposited with the Trustee. Contracts to acquire the bondswere entered into during the period from October 5, 2021 to October 7, 2021.

(2) The Cost of Bonds to Trust is based on the offering side valuation as of the opening of business on the Date of Depositdetermined by the Evaluator, an affiliate of the Sponsor, using offering prices provided by a third-party pricing service on thebasis set forth under “Public Offering--Unit Price”. In accordance with FASB Accounting Standards Codification (“ASC”),ASC 820, Fair Value Measurements and Disclosures, the Trust’s investments are classified as Level 2, which refers tosecurity prices determined using other significant observable inputs. Observable inputs are inputs that other marketparticipants would use in pricing a security. These may include quoted market prices for similar securities, interest rates,prepayment speeds and credit risk. The cost of the bonds to the Sponsor for the Trust is $5,272,306 and the Sponsor’sprofit or (loss) is $1,811.

“+” indicates that the bond was issued by a foreign company.

The Sponsor may have entered into contracts which hedge interest rate fluctuations on certain bonds. The cost of anysuch contracts and the corresponding gain or loss as of the evaluation time of the bonds is included in the Cost toSponsor. Bonds marked by “##” following the maturity date have been purchased on a “when, as and if issued” or“delayed delivery” basis. Interest on these bonds begins accruing to the benefit of Unitholders on their respective dates ofdelivery. Delivery is expected to take place at various dates after the first settlement date.

“#” prior to the coupon rate indicates that the bond was issued at an original issue discount. See “The Trusts--RiskFactors”. The tax effect of bonds issued at an original issue discount is described in “Federal Tax Status”.

(3) “o” indicates that the rating is contingent upon receipt by the rating agency of a policy of insurance obtained by the issuerof the bonds. All ratings are by Standard & Poor’s and Moody’s, respectively, unless otherwise indicated. “*” indicates asecurity rating by Fitch. “NR” indicates that the rating service did not provide a rating for that bond. For a brief descriptionof the ratings see “Description of Ratings” in the Information Supplement.

(4) With respect to any bonds presenting a redemption feature in this column, this is the year in which each bond is initially orcurrently callable and the call price for that year. Each bond continues to be callable at declining prices thereafter (but not belowpar value) except for original issue discount bonds which are redeemable at prices based on the issue price plus the amount oforiginal issue discount accreted to redemption date plus, if applicable, some premium, the amount of which will decline insubsequent years. “S.F.” indicates a sinking fund is established with respect to an issue of bonds. The bonds may also besubject to redemption without premium at any time pursuant to extraordinary optional or mandatory redemptions if certainevents occur. See “The Trusts--Risk Factors”.

(5) Certain bonds have a “make whole” call option and are redeemable in whole or in part at any time at the option of theissuer at a redemption price that is generally equal to the sum of the principal amount of such bond, a “make whole”amount, and any accrued and unpaid interest to the date of redemption. The “make whole” amount is generally equal tothe excess, if any, of (i) the aggregate present value as of the date of redemption of principal being redeemed and theamount of interest (exclusive of interest accrued to the date of redemption) that would have been payable if redemptionhad not been made, determined by discounting the remaining principal and interest at a specified rate (which varies frombond to bond and is generally equal to an average of yields on U.S. Treasury obligations with maturities corresponding tothe remaining life of the bond plus a premium rate) from the dates on which the principal and interest would have beenpayable if the redemption had not been made, over (ii) the aggregate principal amount of the bonds being redeemed. Inaddition, the bonds may also be subject to redemption without premium at any time pursuant to extraordinary optional ormandatory redemptions if certain events occur. See “The Trusts--Risk Factors”.

Underwriting. The Underwriters named below have purchased Units in the following amounts from the Sponsor, the soleand exclusive principal underwriter. See “Public Offering--Sponsor and Underwriter Compensation”.

Name Address Units_________________ _________________ _________________

E D & F Man Capital Markets, Inc. 140 East 45th Street, 42nd Floor, New York, NY 10017 2,730Invesco Capital Markets, Inc. 3500 Lacey Road, Suite 700, Downers Grove, IL 60515-5456 2,070 _________________

4,800 _________________ _________________

7

REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Sponsor and Unitholders of Investment Grade Corporate Trust, 3-7 Year Series 34 (included in Invesco UnitTrusts, Taxable Income Series 637):

Opinion on the Financial Statements

We have audited the accompanying statement of condition (including the related portfolio schedule) of InvestmentGrade Corporate Trust, 3-7 Year Series 34 (included in Invesco Unit Trusts, Taxable Income Series 637 (the “Trust”)) as of October 7, 2021 , and the related notes (collectively referred to as the “financial statements”). In our opinion, the financialstatements present fairly, in all material respects, the financial position of the Trust as of October 7, 2021 , in conformitywith accounting principles generally accepted in the United States of America.

Basis for Opinion

These financial statements are the responsibility of Invesco Capital Markets, Inc., the Sponsor. Our responsibility is toexpress an opinion on the Trust’s financial statements based on our audit. We are a public accounting firm registered withthe Public Company Accounting Oversight Board (United States) (“PCAOB”) and are required to be independent withrespect to the Trust in accordance with the U.S. federal securities laws and the applicable rules and regulations of theSecurities and Exchange Commission and the PCAOB.

We conducted our audit in accordance with the standards of the PCAOB. Those standards require that we plan andperform the audit to obtain reasonable assurance about whether the financial statements are free of materialmisstatement, whether due to error or fraud. The Trust is not required to have, nor were we engaged to perform, an auditof its internal control over financial reporting. As part of our audit we are required to obtain an understanding of internalcontrol over financial reporting but not for the purpose of expressing an opinion on the effectiveness of the Trust’s internalcontrol over financial reporting. Accordingly, we express no such opinion.

Our audit included performing procedures to assess the risks of material misstatement of the financial statements,whether due to error or fraud, and performing procedures that respond to those risks. Such procedures includedexamining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audit alsoincluded evaluating the accounting principles used and significant estimates made by the Sponsor, as well asevaluating the overall presentation of the financial statements. Our procedures included confirmation of cash or anirrevocable letter of credit deposited for the purchase of securities as shown in the statement of condition as of October 7, 2021 by correspondence with The Bank of New York Mellon, Trustee. We believe that our audit provides areasonable basis for our opinion.

/s/ GRANT THORNTON LLP

We have served as the auditor of one or more of the unit investment trusts, sponsored by Invesco Capital Markets,Inc. and its predecessors, since 1976.

New York, New York October 7, 2021

Statement of ConditionAs of the opening of business on October 7, 2021

INVESTMENT IN BONDS

Contracts to purchase bonds (1)(2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . $ 5,274,117 Accrued interest to the first settlement date (1)(2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41,353 Cash (3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42,494 __________________ Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . $ 5,357,964 __________________ __________________

LIABILITY AND INTEREST OF UNITHOLDERS Liability-- Accrued interest payable to Sponsor (1)(2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . $ 41,353 Organization costs (3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42,494 Interest of Unitholders-- Cost to investors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5,421,503 Less: Gross underwriting commission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104,892 Less: Organization costs (3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42,494 __________________ Net interest to Unitholders (1)(2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5,274,117 __________________ Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . $ 5,357,964 __________________ __________________ Units outstanding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4,800 __________________ __________________ Net asset value per Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . $ 1,098.77 __________________ __________________

(1) The value of the bonds is determined by the Evaluator, an affiliate of the Sponsor, using offering prices provided by a third-party pricingservice on the bases set forth under “Public Offering--Unit Price”. The contracts to purchase bonds are collateralized by an irrevocableletter of credit in an amount sufficient to satisfy such contracts.

(2) The Trustee will advance the amount of the net interest accrued to the first settlement date to the Trust for distribution to the Sponsor asthe Unitholder of record as of such date.

(3) A portion of the public offering price represents an amount of cash sufficient to pay for all or a portion of the costs incurred in establishingthe Trust. The amount of these costs are set forth under “Summary of Essential Financial Information--Expenses”. A distribution will bemade as of the earlier of six months after the Date of Deposit or the close of the initial offering period to an account maintained by theTrustee from which the organization expense obligation of the investors will be satisfied. To the extent that actual organization costs of theTrust are greater than the estimated amount, only the estimated organization costs added to the public offering price will be reimbursedto the Sponsor and deducted from the assets of the Trust.

8

THE TRUST

General. Your Trust was created under the laws ofthe State of New York pursuant to a Trust Indenture andAgreement (the “Trust Agreement”), dated the date ofthis prospectus (the “Date of Deposit”) among InvescoCapital Markets, Inc., as Sponsor, Invesco InvestmentAdvisers LLC, as Supervisor and Evaluator, and TheBank of New York Mellon, as Trustee.

Your Trust may be an appropriate medium forinvestors who desire to participate in a portfolio oftaxable bonds with greater diversification than theymight be able to acquire individually. Diversification of aTrust’s assets will not eliminate the risk of loss alwaysinherent in the ownership of bonds. In addition, bondsof the type initially deposited in the portfolio of a Trustare often not available in small amounts and may, in thecase of any privately placed bonds, be available only toinstitutional investors.

On the Date of Deposit, the Sponsor deposited withthe Trustee the aggregate principal amount of bondsindicated in the “Summary of Essential FinancialInformation”. The bonds initially consist of deliverystatements relating to contracts for their purchase andcash, cash equivalents and/or irrevocable letters of creditissued by a financial institution. Thereafter, the Trustee, inexchange for the bonds, delivered to the Sponsorevidence of ownership of the number of Units indicatedunder “Summary of Essential Financial Information”. ATrust that holds primarily bonds within the 3 to 7 yearmaturity range, as described on the cover of theprospectus, is referred to herein as a “Short-Term Trust”.Unless otherwise terminated as provided herein, the TrustAgreement will terminate at the end of the calendar yearprior to the twentieth anniversary of its execution in thecase of a Short-Term Trust.

Each Unit initially offered represents a fractionalundivided interest in the principal and net income of theTrust. The number of Units is determined based upon a$1,000 principal amount of bonds in the Trust per Unit.To the extent that any Units are redeemed to the Trustee,the fractional undivided interest in the Trust representedby each Unit will increase, although the actual interest inthe Trust will remain unchanged. Units will remainoutstanding until redeemed by Unitholders or until thetermination of the Trust Agreement.

Objective and Bond Selection. The objective of aShort-Term Trust is to provide a high level of current

income and to preserve capital by investing in a portfolioprimarily consisting of bonds maturing approximately 3 to7 years from the Date of Deposit. There is, of course, noguarantee that a Trust will achieve its objective. Your Trustmay be an appropriate investment vehicle for investorswho desire to participate in a portfolio of fixed incomebonds with greater diversification than they might be ableto acquire individually.

In selecting bonds for the Trust, the Sponsorconsidered the following factors, among others: (a) theratings criteria applicable to your Trust as listed under“Principal Investment Strategy”; (b) the prices of thebonds relative to other bonds of comparable quality andmaturity; (c) the current income provided by the bonds;(d) the diversification of bonds as to purpose of issue andlocation of issuer and (e) the probability of early return ofprincipal or high legal or event risk. After the Date ofDeposit, a bond may cease to be rated or its rating maybe reduced below the minimum required as of the Dateof Deposit. Neither event requires elimination of a bondfrom a Trust but may be considered in the Sponsor’sdetermination as to whether or not to direct the Trusteeto dispose of the bond (see “Trust Administration--Portfolio Administration”). In particular, the ratings of thebonds in an Investment Grade Corporate Trust could fallbelow “investment grade” (i.e., below “BBB-” or “Baa3”)during the Trust’s life and the Trust could continue to holdthe bonds. See “The Trust--Risk Factors”.

Risk Factors. All investments involve risk. Thissection describes the main risks that can impact thevalue of bonds in your Trust. You should understandthese risks before you invest. If the value of the bondsfalls, the value of your Units will also fall. You can losemoney by investing in a Trust. No one can guaranteethat your Trust will achieve its objective or that yourinvestment return will be positive over any period. TheInformation Supplement, which is available uponrequest, contains a more detailed discussion of risksrelated to your investment.

Corporate Bond Risk. Corporate bonds, which aredebt instruments issued by corporations to raise capital,have priority over preferred securities and commonstock in an issuer’s capital structure, but may besubordinated to an issuer’s other debt instruments. Themarket value of a corporate bond may be affected byfactors directly related to the issuer, such as investors’perceptions of the creditworthiness of the issuer, the

9

issuer’s financial performance, perceptions of the issuerin the market place, performance of the issuer’smanagement, the issuer’s capital structure, the use offinancial leverage and demand for the issuer’s goodsand services, and by factors not directly related to theissuer such as general market liquidity. The market valueof corporate bonds generally may be expected to riseand fall inversely with interest rates, and as a result,corporate bonds may lose value in a rising-rateenvironment. To the extent your Trust holds belowinvestment grade corporate bonds, such bonds areoften high risk and have speculative characteristics andmay be particularly susceptible to adverse issuer-specific developments.

Current economic conditions. The economic recessionin the United States which began in 2007 technically cameto an end in June of 2009, however the U.S. and globaleconomies continue to feel the effects of this recessionaryperiod, including increased unemployment and below-average levels of economic activity. The U.S. and otherforeign governments have taken extraordinary steps tocombat the effects of the economic crisis, however theultimate impact of these measures is unknown and cannotbe predicted. While the U.S. Federal Reserve formallyconcluded its quantitative easing program, there continuesto be uncertainty concerning potential future changes tothe federal funds rate. On August 5, 2011, Standard &Poor’s Rating Services downgraded the long-termsovereign credit rating of the United States of America toAA+ from AAA, citing the prolonged controversy overraising the statutory debt ceiling and the related fiscalpolicy debate. Any substantial change in general marketconditions may result in sudden and significant valuationincreases or declines in your Trust’s holdings.

Furthermore, a recent outbreak of a respiratory diseasecaused by a novel coronavirus (“COVID-19”), first detectedin China in December 2019, has spread globally in a shortperiod of time. COVID-19 has resulted in the disruption of,and delays in, production and supply chains and thedelivery of healthcare services and processes, as well asthe cancellation of organized events and educationalinstitutions, a decline in consumer demand for certaingoods and services, and general concern and uncertainty.In response, governments and businesses world-wide,including the United States, have taken aggressivemeasures, including closing borders, restrictinginternational and domestic travel, imposing prolongedquarantines of large populations, and financial support of

the economy and financial markets. COVID-19 and itseffects have contributed to increased volatility in globalmarkets, severe loses, liquidity constraints, and loweredyields; the duration of such effects cannot yet bedetermined but could be present for an extended periodof time. The effects that COVID-19 may have on certainsectors and industries are uncertain and may adverselyaffect the value of your Trust.

Market risk is the risk that the value of the bonds in yourTrust will fluctuate. This could cause the value of your Unitsto fall below your original purchase price or below the parvalue. Market value fluctuates in response to variousfactors. These can include changes in interest rates,inflation, the financial condition of a bond’s issuer or insurer,perceptions of the issuer or insurer, or ratings on a bond.Certain geopolitical and other events, includingenvironmental events and public health events such asepidemics and pandemics, may have a global impact andadd to instability in world economies and marketsgenerally. Changing economic, political or financial marketconditions in one country or geographic region couldadversely affect the market value of the securities held byyour Trust in a different country or geographic region dueto increasingly interconnected global economies andfinancial markets. Even though the Supervisor supervisesyour portfolio, you should remember that no one managesyour portfolio. Your Trust will not sell a bond solely becausethe market value falls as is possible in a managed fund.

Foreign securities risk. Investing in foreign securitiestypically involves more risks than investing in securities ofUnited States issuers. These risks can increase thepotential for losses in the Trust and affect its Unit price.These risks may include risks such as losses due topolitical, economic and social developments, internationaltrade conditions, foreign taxes (including withholdingtaxes), restrictions on foreign investments or exchange ofsecurities, foreign currency fluctuations or restriction onexchange or repatriation of currencies.

The political, economic and social structures of someforeign countries may be less stable and more volatilethan those in the U.S., and investments in these countriesmay be subject to the risks of internal and externalconflicts, currency devaluations, foreign ownershiplimitations and tax increases. It is possible that agovernment may take over the assets or operations of acompany or impose restrictions on the exchange orexport of currency or other assets. Some countries also

10

may have different legal systems that may make it difficultfor the Trust to exercise investor rights, and pursue legalremedies with respect to its foreign investments.Diplomatic and political developments, including rapidand adverse political changes, social instability, regionalconflicts, terrorism and war, could affect the economies,industries, and securities and currency markets, and thevalue of the Trust’s investments, in non-U.S. countries. Noone can predict the impact that these factors could haveon the Trust’s portfolio securities.

Foreign companies may not be subject to the samedisclosure, accounting, auditing and financial reportingstandards and practices as U.S. companies. Thus, theremay be less information publicly available about foreigncompanies than about most U.S. companies.

Certain foreign securities may be less liquid (harder tosell) and more volatile than many U.S. securities. Thismeans the Trust may at times be unable to sell foreignsecurities in a timely manner or at favorable prices.

In addition, for foreign securities of European issuers,the departure of any European Union (“EU”) memberfrom use of the Euro could lead to serious disruptionsto foreign exchanges, operations and settlements, whichmay have an adverse effect on European issuers. Thereis particular uncertainty regarding the state of the EUfollowing the United Kingdom’s (“U.K.”) initiation onMarch 27, 2017, of the process to exit from the EU(“Brexit”). As of January 31, 2020, the U.K. has officiallyexited the EU, and while a trade deal was negotiatedand provisionally went into effect on January 1, 2021,the effect that Brexit may have on European issuers orcompanies with a significant European presence isuncertain. No one can predict the impact that thesefactors could have on the securities held by the Trust.

Interest rate risk is the risk that the value of bonds willfall if interest rates increase. Bonds typically fall in valuewhen interest rates rise and rise in value when interestrates fall. Bonds with longer periods before maturity areoften more sensitive to interest rate changes. In a lowinterest rate environment risks associated with risingrates are heightened. Due to the current period ofhistorically low rates, the securities held by the Trust maybe subject to a greater risk of rising interest rates thanwould normally be the case. The negative impact onfixed income securities from any interest rate increasescould be swift and significant.

Credit risk is the risk that a bond’s issuer or insurer isunable to meet its obligation to pay principal or intereston the bond.

Call risk is the risk that the issuer prepays or “calls” abond before its stated maturity. An issuer might call a bondif interest rates fall and the bond pays a higher interest rateor if it no longer needs the money for the original purpose.If an issuer calls a bond, your Trust will distribute theprincipal to you but your future interest distributions will fall.You might not be able to reinvest this principal at as higha yield. A bond’s call price could be less than the priceyour Trust paid for the bond and could be below thebond’s par value. This means that you could receive lessthan the amount you paid for your Units. If enough bondsin your Trust are called, your Trust could terminate early.

Some or all of the bonds may also be subject toextraordinary optional or mandatory redemptions ifcertain events occur, such as certain changes in taxlaws, the substantial damage or destruction by fire orother casualty of the project for which the proceeds ofthe bonds were used, and various other events. The callprovisions are described in general terms in the“Redemption Feature” column of the “Portfolio” section,and the notes thereto.

Bond quality risk is the risk that a bond will fall in valueif a rating agency decreases the bond’s rating.

Bond concentration risk is the risk that your Trust isless diversified because it concentrates in a particulartype of bond. When a certain type of bond makes up25% or more of a Trust, the Trust is considered to be“concentrated” in that bond type. During the life of yourTrust, the relative weighting or composition of your Trustmay change for reasons including but not limited tobond price fluctuations, Unit redemption activity, as wellas the calling or maturing of bonds. Accordingly, thefluctuations in the relative weighting or composition ofyour Trust may result in concentrations (25% or more ofa portfolio’s assets) in bonds of a particular type, industryand/or geographic region. The different bond types aredescribed in the following sections.

Reduced diversification risk is the risk that your Trustwill become smaller and less diversified as bonds aresold, are called or mature. This could increase your riskof loss and increase your share of Trust expenses.

Liquidity risk is the risk that the value of a bond will fallif trading in the bond is limited or absent, thereby

11

adversely affecting the Trust’s net asset value. The marketfor certain investments may become less liquid or illiquiddue to adverse changes in the conditions of a particularissuer or due to adverse market or economic conditions.In the absence of a liquid trading market for a particularsecurity, the price at which such security may be sold tomeet redemptions, as well as the value of the Units of yourTrust, may be adversely affected. No one can guaranteethat a liquid trading market will exist for any bond becausethese bonds generally trade in the over-the-countermarket (they are not listed on a securities exchange).Because of the difficulties currently being experienced bymany companies in the financial services industry, manymarkets are experiencing substantially reduced liquidity.As a result of such illiquidity, the Trustee may have to sellother or additional bonds if necessary to satisfyredemption requests.

Litigation and legislation risk is the risk that futurelitigation or legislation could affect the value of your Trust.Litigation could challenge an issuer’s authority to issueor make payments on bonds.

Corporate Bond Industry Risks. Your Trust mayinvest significantly in bonds of certain industries. Anynegative impact on the related industry will have a greaterimpact on the value of Units than on a portfolio diversifiedover several industries. You should understand the risksof these industries before you invest.

Communications Issuers. Your Trust may investsignificantly in bonds issued by communicationscompanies, which includes telecommunicationscompanies. This sector is primarily characterized byextensive government regulation and intensecompetition.

Companies in the telecommunications industryallocate significant resources in efforts to comply withapplicable government regulations. Telecommunicationscompanies operating in the U.S. must comply withapplicable state and federal regulations, including thoseof the Federal Communications Commission. The costsof complying with governmental regulations, delays orfailure to receive required regulatory approvals or theenactment of new adverse regulatory requirements maynegatively affect the business of telecommunicationscompanies. Recent industry consolidation trends maylead to increased regulation in primary markets.Internationally, telecommunications companies may faceregulatory challenges such as securing pre-marketing

clearance of products and prices, which may bearbitrary and unpredictable. U.S. federal and stategovernments regulate permitted rates of return and thekinds of services that a company may offer. U.S. federallegislation governing the telecommunications industrymay become subject to judicial review and additionalinterpretation, which may adversely affect certaintelecommunications issuers.

The competitive landscape in the telecommunicationssector is intense and constantly evolving. The productsand services of these companies may become outdatedvery rapidly. A company’s performance can be hurt if thecompany fails to keep pace with technological advances.At the same time, demand for some telecommunicationsservices remains weak, as several key markets areoversaturated and many customers can choose betweenseveral service providers and technology platforms. Tomeet increasing competition, companies may have tocommit substantial capital, particularly in the formulationof new products and services using new technologies. Asa result, many companies have been compelled to cutcosts by reducing their workforce, outsourcing,consolidating and/or closing existing facilities and divestinglow selling product lines. Certain telecommunicationscompanies may be engaged in fierce competition for ashare of the market of their products and may have highercosts, including liabilities associated with the medical,pension and postretirement expenses of their workforce,than their competitors. As a result, competitive pressuresare intense and the stocks are subject to rapid pricevolatility. Moreover, continued consolidation in this industrycould create integration expenses and delay, andconsequent management diversion of attention away fromongoing operations and related risks, among other factors,could result in the failure of these companies to realizeexpected cost savings or synergies.

Several high-profile bankruptcies of largetelecommunications companies in the past haveillustrated the potentially unstable condition of thetelecommunications industry. High debt loads thatwere accumulated during the industry growth spurt ofthe 1990s caught up to the industry, causing debt andstock prices to trade at distressed levels for manytelecommunications companies and increasing thecost of capital for needed additional investment.Furthermore, certain companies involved in theindustry have also faced scrutiny for allegedaccounting irregularities that may have led to the

12

overstatement of their financial results, and othercompanies in the industry may face similar scrutiny.Moreover, some companies have begun the processof emerging from bankruptcy and may have reducedlevels of debt and other competitive advantages overother telecommunications companies. Due to theseand other factors, the risk level of owning the securitiesof telecommunications companies remains substantialand may continue to rise.

Consumer Discretionary and Consumer StaplesIssuers. Your Trust may invest significantly in bondsissued by companies that manufacture or sell variousconsumer products. General risks of these companiesinclude the overall state of the economy, intensecompetition and consumer spending trends. A decline inthe economy which results in a reduction of consumers’disposable income can negatively impact spendinghabits. Global factors including political developments,imposition of import controls, fluctuations in oil prices,and changes in exchange rates may adversely affectissuers of consumer products and services.

Competitiveness in the retail industry may requirelarge capital outlays for the installation of automatedcheckout equipment to control inventory, track the saleof items and gauge the success of sales campaigns.Retailers who sell their products over the Internet havethe potential to access more consumers, but mayrequire sophisticated technology to remaincompetitive. Changes in demographics and consumertastes can also affect the demand for, and the successof, consumer products and services in themarketplace. Consumer products and servicescompanies may be subject to government regulationaffecting their products and operations which maynegatively impact performance. Tobacco companiesmay be adversely affected by new laws, regulationsand litigation.

Energy Issuers. Your Trust may invest significantly inbonds issued by energy companies. Energy companiescan be significantly impacted by fluctuations in the pricesof energy fuels, such as crude oil, natural gas, and otherfossil fuels. Extended periods of low energy fuel prices canhave a material adverse impact on an energy company’sfinancial condition and results of operations. The prices ofenergy fuels can be materially impacted by generaleconomic conditions, demand for energy fuels, industryinventory levels, production quotas or other actions that

might be imposed by the Organization of PetroleumExporting Countries (OPEC), weather-related disruptionsand damage, competing fuel prices, and geopolitical risks.Recently, the price of crude oil, natural gas and other fossilfuels has declined substantially and experienced significantvolatility, which has adversely impacted energy companiesand their stock prices and dividends. The price of energyfuels may decline further and have further adverse effectson energy companies.

Some energy companies depend on their ability to findand acquire additional energy reserves. The explorationand recovery process involves significant operatinghazards and can be very costly. An energy company hasno assurance that it will find reserves or that any reservesfound will be economically recoverable.

The energy industry also faces substantial governmentregulation, including environmental regulation regarding airemissions and disposal of hazardous materials. Theseregulations may increase costs and limit production andusage of certain fuels. Additionally, governments havebeen increasing their attention to issues related togreenhouse gas (“GHG”) emissions and climate change,and regulatory measures to limit or reduce GHG emissionsare currently in various stages of discussion orimplementation. GHG emissions-related regulations couldsubstantially harm energy companies, including byreducing the demand for energy fuels and increasingcompliance costs. Energy companies also face risksrelated to political conditions in oil producing regions (suchas the Middle East). Political instability or war in theseregions could negatively impact energy companies.

The operations of energy companies can bedisrupted by natural or human factors beyond thecontrol of the energy company. These includehurricanes, floods, severe storms, and other weatherevents, civil unrest, accidents, war, earthquakes, fire,political events, systems failures, and terrorist attacks,any of which could result in suspension of operations.Energy companies also face certain hazards inherent tooperating in their industry, such as accidental releasesof energy fuels or other hazardous materials, explosions,and mechanical failures, which can result inenvironmental damage, loss of life, loss of revenues,legal liability and/or disruption of operations.

Financials Issuers. Your Trust may invest significantlyin bonds issued by financial services companies.Companies in the financial services industry include, but

13

are not limited to, companies involved in activities suchas banking, mortgage finance, consumer finance,specialized finance, industrial finance and leasing,investment banking and brokerage, asset managementand custody, corporate lending, insurance, and financialinvestment. In general, financial services issuers aresubstantially affected by changes in economic andmarket conditions, including: the liquidity and volatilitylevels in the global financial markets; interest rates, aswell as currency and commodities prices; investorsentiment; the rate of corporate and consumer defaults;inflation and unemployment; the availability and cost ofcapital and credit; exposure to various geographicmarkets or in commercial and residential real estate;competition from new entrants in their fields of business;extensive government regulation; and the overall healthof the U.S. and international economies. Due to the widevariety of companies in the financial services sector, theymay behave and react in different ways in response tochanges in economic and market conditions.

Companies in the financial services sector are subjectto several distinct risks. Such companies may be subjectto systematic risk, which may result due to factorsoutside the control of a particular financial institution —like the failure of another, significant financial institutionor material disruptions to the credit markets — thatcould adversely affect the ability of the financial institutionto operate normally or may impair its financial condition.Financial services companies are typically affected bychanges in interest rates, and may be disproportionallyaffected as a result of volatile and/ or rising interest rates.

Certain financial services companies may themselveshave concentrated portfolios, which makes themvulnerable to economic conditions that affect thatindustry. Companies in this sector are often subject tocredit risk, meaning they may have exposure toinvestments or agreements which under certaincircumstances may lead to losses.

The financial services sector may be adverselyaffected by global developments including recessionaryconditions, deterioration in the credit markets andconcerns over sovereign debt. This may increase thecredit risk, and possibility of default, of bonds issuedby such institutions faced with these problems. Inaddition, the liquidity of certain debt instruments maybe reduced or eliminated due to the lack of availablemarket makers. There can be no assurance that the

risks associated with investment in financial servicesissuers will decrease even assuming that the U.S.and/or foreign governments and agencies take stepsto address problems that may arise.

Most financial services companies are subject toextensive governmental regulation, which limits theiractivities and may affect their ability to earn a profit froma given line of business. This also exposes financialservices issuers to regulatory risk, where certain financialservices companies may suffer setbacks if regulatorschange the rules under which they operate. Challengingeconomic and political conditions, along with increasedpublic scrutiny during the past several years, led to newlegislation and increased regulation in the U.S. andabroad, creating additional difficulties for financialinstitutions. Regulatory initiatives and requirements thatwere proposed around the world may be inconsistent ormay conflict with previous regulations to which financialservices issuers were subject, thereby resulting in highercompliance and legal costs, as well as the potential forhigher operational, capital and liquidity costs. Proposedor enacted regulations may further limit the amounts andtypes of loans and other financial commitments certainfinancial services issuers can make, and further, maylimit the interest rates and fees they can charge, theprices they can charge and the amount of capital theymust maintain. These laws and regulations may affectthe manner in which a particular financial institution doesbusiness and the products and services it may provide.Increased regulation may restrict a company’s ability tocompete in its current businesses or to enter into oracquire new businesses. New regulations may reduceor limit a company’s revenue or impose additional fees,limit the scope of their activities, increase assessmentsor taxes on those companies and intensify regulatorysupervision, adversely affecting business operations orleading to other negative consequences.

Among the most prominent pieces of U.S. legislationfollowing the 2008 financial crisis was the Dodd-Frank WallStreet Reform and Consumer Protection Act (the “Dodd-Frank Act”), enacted into federal law on July 21, 2010. TheDodd-Frank Act included reforms and refinements tomodernize existing laws to address emerging risks andissues in the nation’s evolving financial system. It alsoestablished entirely new regulatory regimes, including inareas such as systemic risk regulation, over-the-counterderivatives market oversight, and federal consumerprotection. The Dodd-Frank Act intended to cover virtually

14

all participants in the financial services industry for yearsto come, including banks, thrifts, depository institutionholding companies, mortgage lenders, insurancecompanies, industrial loan companies, broker-dealers andother securities and investment advisory firms, privateequity and hedge funds, consumers, numerous federalagencies and the federal regulatory structure. In particular,certain provisions of the Dodd-Frank Act increased thecapital requirements of certain financial servicescompanies supervised by the Federal Reserve, resultingin such companies incurring generally higher depositpremiums. The Economic Growth, Regulatory Relief andConsumer Protection Act (the “Relief Act”), enacted intofederal law on May 23, 2018, introduced changes toseveral aspects of the U.S. financial industry. The ReliefAct dilutes some of the stringent regulations imposed bythe Dodd-Frank Act and aims to make things easier forsmall- and medium-sized U.S. banks – however, all bankswill remain regulated. The Relief Act will relieve small- andmedium-sized banks from major regulatory compliancecosts linked with stricter scrutiny.

The Relief Act may lead to further deregulation androll-back of the Dodd-Frank Act and the Sponsor isunable to predict the impact that such changes mayhave on financial services issuers.

Financial services companies operating in foreigncountries are also subject to regulatory and interest rateconcerns. In particular, government regulation in certainforeign countries may include controls on interest rates,credit availability, prices and currency transfers. Thedeparture of any EU member from use of the Euro couldlead to serious disruptions to foreign exchanges,operations and settlements, which may have an adverseeffect on financial services issuers. There is particularuncertainty regarding the state of the EU following Brexit.As of January 31, 2020, the U.K. has officially exited theEU, and while a trade deal was negotiated andprovisionally went into effect on January 1, 2021, Brexitmarks the first time a significant member of the EU willhave left. The effect that Brexit may have on the globalfinancial markets or on the financial services companiesin your Trust is uncertain.

Commercial banks (including “money center”regional and community banks), savings and loanassociations and holding companies of the foregoingare especially subject to adverse effects of volatileinterest rates, concentrations of loans in particular

industries or classifications (such as real estate, energy,or sub-prime mortgages), and significant competition.The profitability of these businesses is to a significantdegree dependent on the availability and cost of capitalfunds. Economic conditions in the real estate marketmay have a particularly strong effect on certain banksand savings associations. Commercial banks andsavings associations are subject to extensive federaland, in many instances, state regulation. Neither suchextensive regulation nor the federal insurance ofdeposits ensures the solvency or profitability ofcompanies in this industry, and there is no assuranceagainst losses in securities issued by such companies.

Insurance companies are particularly subject togovernment regulation and rate setting, potentialantitrust and tax law changes, and industry-wide pricingand competition cycles. Property and casualty insurancecompanies also may be affected by weather, terrorism,long-term climate changes, and other catastrophes. Lifeand health insurance companies may be affected bymortality and morbidity rates, including the effects ofepidemics. Individual insurance companies may beexposed to reserve inadequacies, problems ininvestment portfolios (for example, real estate or “junk”bond holdings) and failures of reinsurance carriers.

Many of the investment considerations discussed inconnection with banks and insurance companies alsoapply to other financial services companies. Thesecompanies are subject to extensive regulation, rapidbusiness changes, and volatile performance dependenton the availability and cost of capital and prevailinginterest rates and significant competition. Generaleconomic conditions significantly affect thesecompanies. Credit and other losses resulting from thefinancial difficulty of borrowers or other third parties havea potentially adverse effect on companies in this industry.Investment banking, securities brokerage andinvestment advisory companies are particularly subjectto government regulation and the risks inherent insecurities trading and underwriting activities.

The financial condition of customers, clients andcounterparties, including other financial institutions,could adversely affect financial services issuers. Financialservices issuers are interrelated as a result of marketmaking, trading, clearing or other counterpartyrelationships. Many of these transactions exposefinancial services issuers to credit risk as a result of the

15

actions of, or deterioration in, the commercialsoundness of other counterparty financial institutions.Economic and market conditions may increase creditexposures due to the increased risk of customer, clientor counterparty default. Downgrades to the creditratings of financial services issuers could have a negativeeffect on liquidity, cash flows, competitive position,financial condition and results of operations bysignificantly limiting access to funding or capital markets,increasing borrowing costs or triggering increasedcollateral requirements. Financial services issuers facesignificant legal risk, both from regulatory investigationsand proceedings, as well as private actions. Profitmargins of these companies continue to shrink due tothe commoditization of traditional businesses, newcompetitors, capital expenditures on new technologyand the pressure to compete globally.

Health Care Issuers. Your Trust may invest significantlyin bonds issued by health care companies. These issuersinclude companies involved in advanced medical devicesand instruments, drugs and biotechnology, managedcare, hospital management/health services and medicalsupplies. These companies face substantial governmentregulation and approval procedures. General risks ofhealth care companies include extensive competition,product liability litigation and evolving governmentregulation.

On March 30, 2010, the Health Care and EducationReconciliation Act of 2010 (incorporating the PatientProtection and Affordable Care Act, collectively the“Act”) was enacted into law. The Act continues to havea significant impact on the health care sector throughthe implementation of a number of reforms in a complexand ongoing process, with varying effective dates.Significant provisions of the Act include the introductionof required health care coverage for most Americans,significant expansion in the number of Americans eligiblefor Medicaid, modification of taxes and tax credits in thehealth care sector, and subsidized insurance for low tomiddle income families. The Act also provides for morethorough regulation of private health insuranceproviders, including a prohibition on the denial ofcoverage due to pre-existing conditions. In late 2017,along with the passage of sweeping tax reform,legislation was passed which eliminated the individualmandate (a penalty for failure to obtain a minimum levelof health insurance coverage) beginning in 2019. It isestimated that the repeal of the individual mandate will

cause a significant amount of people to be uninsuredwhich may have an adverse effect on insurancepremiums and federal subsidies. The Sponsor is unableto predict the full impact of the Act, or of its potentialrepeal or modification, on the Securities in your Trust.

As illustrated by the Act, Congress may from time totime propose legislative action that will impact the healthcare sector. The proposals may span a wide range oftopics, including cost and price controls (which mayinclude a freeze on the prices of prescription drugs),incentives for competition in the provision of health careservices, promotion of pre-paid health care plans andadditional tax incentives and penalties aimed at the healthcare sector. The government could also reduce fundingfor health care related research.

Drug and medical products companies also face therisk of increasing competition from new products orservices, generic drug sales, product obsolescence,increased government regulation, termination of patentprotection for drug or medical supply products and therisk that a product will never come to market. Theresearch and development costs of bringing a new drugor medical product to market are substantial. Thisprocess involves lengthy government review with noguarantee of approval. These companies may havelosses and may not offer proposed products for severalyears, if at all. The failure to gain approval for a new drugor product can have a substantial negative effect on acompany and its stock. The goods and services of healthcare issuers are also subject to risks of malpracticeclaims, product liability claims or other litigation.

Health care facility operators face risks related todemand for services, the ability of the facility to providerequired services, an increased emphasis on outpatientservices, confidence in the facility, managementcapabilities, competitive forces that may result in pricediscounting, efforts by insurers and government agenciesto limit rates, expenses, the cost and possibleunavailability of malpractice insurance, and terminationor restriction of government financial assistance (such asMedicare, Medicaid or similar programs).

Industrials Issuers. Your Trust may invest significantlyin bonds issued by industrials companies. General risksof industrials companies include the general state of theeconomy, intense competition, imposition of importcontrols, volatility in commodity prices, currencyexchange rate fluctuation, consolidation, labor relations,

16

domestic and international politics, excess capacity andconsumer spending trends. Companies in the industrialssector may be adversely affected by liability forenvironmental damage and product liability claims.Capital goods companies may also be significantlyaffected by overall capital spending and leverage levels,economic cycles, technical obsolescence, delays inmodernization, limitations on supply of key materials,depletion of resources, government regulations,government contracts and e-commerce initiatives.

Industrials companies may also be affected by factorsmore specific to their individual industries. Industrialmachinery manufacturers may be subject to declines incommercial and consumer demand and the need formodernization. Aerospace and defense companies maybe influenced by decreased demand for new equipment,aircraft order cancellations, disputes over or ability toobtain or retain government contracts, changes ingovernment budget priorities, changes in aircraft-leasingcontracts and cutbacks in profitable business travel. Thenumber of housing starts, levels of public and non-residential construction including weakening demand fornew office and retail space, and overall constructionspending may adversely affect construction materials andequipment manufacturers. Stocks of transportationcompanies are cyclical and can be significantly affectedby economic changes, fuel prices and insurance costs.Transportation companies in certain countries may alsobe subject to significant government regulation andoversight, which may negatively impact their businesses.

Materials Issuers. Your Trust may invest significantly inbonds issued by companies in the materials industry.Companies in the materials sector could be adverselyaffected by commodity price volatility, exchange rates,import controls and increased competition. Production ofmaterials often exceeds demand as a result ofoverbuilding or economic downturns, leading to poorinvestment returns. Companies in the materials sector areat risk for environmental damage and product liabilityclaims. Companies in the materials sector may beadversely affected by depletion of resources, technicalprogress, labor relations, and governmental regulations.

Real Estate Issuers. Your Trust may invest significantlyin bonds issued by real estate companies. You shouldunderstand the risks of real estate companies before youinvest. Many factors can have an adverse impact on theperformance of a particular real estate company, including

its cash available for distribution, the credit quality of aparticular company or the real estate industry generally.The success of real estate companies depends on variousfactors, including the occupancy and rent levels,appreciation of the underlying property and the ability toraise rents on those properties. Economic recession,overbuilding, tax law changes, higher interest rates orexcessive speculation can all negatively impact thesecompanies, their future earnings and share prices.

Risks associated with real estate companies include,among other factors,

• general U.S. and global as well as localeconomic conditions,

• decline in real estate values,

• the financial health of tenants,

• over-building and increased competition fortenants,

• over-supply of properties for sale,

• changing demographics,

• changes in interest rates, tax rates and otheroperating expenses,

• changes in government regulations,

• faulty construction and the ongoing need forcapital improvements,

• regulatory and judicial requirements,including relating to liability for environmentalhazards,

• changes in neighborhood values and buyerdemand, and

• the unavailability of construction financing ormortgage loans at rates acceptable todevelopers.

Variations in rental income and space availability andvacancy rates in terms of supply and demand areadditional factors affecting real estate generally and realestate companies in particular. Properties owned by acompany may not be adequately insured against certainlosses and may be subject to significant environmentalliabilities, including remediation costs.

You should also be aware that real estate companiesmay not be diversified and are subject to the risks offinancing projects.

17

Because of the structure of certain real estatecompanies, and legal requirements in many countries thatthese companies distribute a certain minimum amount oftheir taxable income to shareholders annually, real estatecompanies often require frequent amounts of new funding,through both borrowing money and issuing stock. Thus,many real estate companies historically have frequentlyissued substantial amounts of new equity shares (orequivalents) to purchase or build new properties. This mayhave adversely affected security market prices. Bothexisting and new share issuances may have an adverseeffect on these prices in the future, especially whencompanies continue to issue stock when real estate pricesare relatively high and stock prices are relatively low.

Information Technology Issuers. Your Trust may investsignificantly in bonds issued by companies in thetechnology sector which includes information technologycompanies. The information technology sector includescompanies that are involved in computer and businessservices, enterprise software/technical software, Internetand computer software, Internet-related services,networking and telecommunications equipment,telecommunications services, electronics products, serverhardware, computer hardware and peripherals,semiconductor capital equipment and semiconductors.These companies face risks related to rapidly changingtechnology, rapid product obsolescence, cyclical marketpatterns, evolving industry standards and frequent newproduct introductions.

Companies in this sector face risks from rapid changesin technology, competition, dependence on certainsuppliers and supplies, rapid obsolescence of productsor services, patent termination, frequent new productsand government regulation. These companies can alsobe adversely affected by interruption or reduction insupply of components or loss of key customers andfailure to comply with certain industry standards.

An unexpected change in technology can have asignificant negative impact on a company. The failure of acompany to introduce new products or technologies orkeep pace with rapidly changing technology can have anegative impact on the company’s results. Certaintechnology companies may also be smaller and/or lessexperienced companies with limited product lines, marketsor resources. Stocks of some Internet companies havehigh price-to-earnings ratios with little or no earningshistories. Technology stocks tend to experience

substantial price volatility and speculative trading.Announcements about new products, technologies,operating results or marketing alliances can cause stockprices to fluctuate dramatically. At times, however, extremeprice and volume fluctuations are unrelated to theoperating performance of a company. This can impactyour ability to redeem your Units at a price equal to orgreater than what you paid.

Utility Issuers. The Trust may invest significantly inbonds issued by utility companies or in companies relatedto the utility industry. Many utility companies, especiallyelectric and gas and other energy related utility companies,are subject to various uncertainties, including:

• Risks of increases in fuel and other operatingcosts;

• Restrictions on operations and increasedcosts and delays as a result of environmental,nuclear safety and other regulations;

• Regulatory restrictions on the ability to passincreasing wholesale costs along to the retailand business customer;

• Coping with the general effects of energyconservation;

• Technological innovations which may renderexisting plants, equipment or productsobsolete;

• The effects of unusual, unexpected orabnormal local weather

• Maturing markets and difficulty in expandingto new markets due to regulatory and otherfactors;

• The potential impact of natural or manmadedisasters;

• Difficulty obtaining adequate returns oninvested capital, even if frequent rateincreases are approved by public servicecommissions;

• The high cost of obtaining financing duringperiods of inflation;

• Difficulties of the capital markets in absorbingutility debt and equity securities;

• Increased competition; and

• International politics.

18

Any of these factors, or a combination of thesefactors, could affect the supply of or demand for energy,such as electricity or natural gas, or water, or the abilityof the issuers to pay for such energy or water whichcould adversely affect the profitability of the issuers of thebonds and the performance of the Trust.

Utility companies are subject to extensive regulationat the federal level in the United States, and many areregulated at the state level as well. The value of utilitycompany stocks may decline because governmentalregulation affecting the utilities industry can change. Thisregulation may prevent or delay the utility company frompassing along cost increases to its customers, whichcould hinder the utility company’s ability to meet itsobligations to its suppliers and could lead to the takingof measures, including the acceleration of obligations orthe institution of involuntary bankruptcy proceedings, byits creditors against such utility company. Furthermore,regulatory authorities, which may be subject to politicaland other pressures, may not grant future rate increases,or may impose accounting or operational policies, anyof which could adversely affect a company’s profitabilityand its stock price.

Certain utility companies have experienced full orpartial deregulation in recent years. These utilitycompanies are frequently more similar to industrialcompanies in that they are subject to greatercompetition and have been permitted by regulators todiversify outside of their original geographic regions andtheir traditional lines of business. These opportunitiesmay permit certain utility companies to earn more thantheir traditional regulated rates of return. Somecompanies, however, may be forced to defend their corebusiness and may be less profitable. While regulatedproviders tend to have regulated returns, non-regulatedproviders’ returns are not regulated and generally aremore volatile. These developments have reducedstability of cash flows in those states with non-regulatedproviders and could impact the short-term earningspotential of some in this industry. These trends have alsomade shares of some utility companies less sensitive tointerest rate changes but more sensitive to changes inrevenue and earnings and caused them to reduce theratio of their earnings they pay out as dividends.

Certain utilities companies face risks associated withthe operation of nuclear facilities for electric generation,including, among other considerations, litigation, the

problems associated with the use of radioactive materialsand the effects of natural or man-made disasters. Ingeneral, certain utility companies may face additionalregulation and litigation regarding their power plantoperations, increased costs from new or greaterregulation of these operations, and expenses related tothe purchase of emissions control equipment.

More About the Bonds. In addition to describingthe purpose of the bonds, other information about thebonds is also included in the “Portfolio” and notesthereto. This information relates to other characteristicsof the bonds. This section briefly describes some ofthese characteristics.

Original issue discount bonds were initially issued ata price below their face (or par) value. These bondstypically pay a lower interest rate than comparablebonds that were issued at or above their par value. In astable interest rate environment, the market value ofthese bonds tends to increase more slowly in early yearsand in greater increments as the bonds approachmaturity. The issuers of these bonds may be able to callor redeem a bond before its stated maturity date and ata price less than the bond’s par value.

Zero coupon bonds are a type of original issue discountbond. These bonds do not pay any current interest duringtheir life. If an investor owns this type of bond, the investorhas the right to receive a final payment of the bond’s parvalue at maturity. The price of these bonds often fluctuatesgreatly during periods of changing market interest ratescompared to bonds that make current interest payments.The issuers of these bonds may be able to call or redeema bond before its stated maturity date and at a price lessthan the bond’s par value.

“When, as and if issued” bonds are bonds that tradebefore they are actually issued. This means that theSponsor can only deliver them to your Trust “when, asand if” the bonds are actually issued. Delivery of thesebonds may be delayed or may not occur. Interest onthese bonds does not begin accruing to your Trust untilthe Sponsor delivers the bond to the Trust. You mayhave to adjust your tax basis if the Sponsor delivers anyof these bonds after the expected delivery date. Anyadjustment would reflect interest that accrued betweenthe time you purchased your Units and the delivery ofthe bonds to your Trust. This could lower your first yearestimated current return. You may experience gains or

19

losses on these bonds from the time you purchase Unitseven though your Trust has not yet received them.

In order to acquire certain bonds, it may be necessaryfor the Sponsor or Trustee to pay amounts coveringaccrued interest on the bonds which exceed theamounts which will be made available through cashfurnished by the Sponsor on the Date of Deposit. Thiscash may exceed the interest which would accrue to theFirst Settlement Date. The Trustee has agreed to pay forany amounts necessary to cover any excess and will bereimbursed when funds become available from interestpayments on the related bonds. Also, since interest onany “when, as and if issued” bonds does not beginaccruing to the benefit of Unitholders until the date ofdelivery, the Trustee may reduce its fee and pay Trustexpenses in order to maintain or approach the sameestimated net annual interest income during the first yearof the Trust’s operations as described under “Summaryof Essential Financial Information”.

No FDIC Guarantee. An investment in your Trustis not a deposit of any bank and is not insured orguaranteed by the Federal Deposit InsuranceCorporation or any other government agency.

ESTIMATED CURRENT AND LONG-TERM RETURNS

The Estimated Current Return and the EstimatedLong-Term Return as of the Date of Deposit are set forthon the cover of the prospectus. Estimated CurrentReturn is calculated by dividing the estimated net annualinterest income per Unit by the Public Offering Price. Theestimated net annual interest income per Unit will varywith changes in fees and expenses of your Trust and withthe principal prepayment, default (if any), redemption,maturity, exchange or sale of bonds. The Public OfferingPrice will vary with changes in the price of the bonds.Accordingly, there is no assurance that the presentEstimated Current Return will be realized in the future.Estimated Long-Term Return is calculated using aformula which (1) takes into consideration, anddetermines and factors in the relative weightings of, themarket values, yields (which takes into account theamortization of premiums and the accretion of discounts)and estimated retirements of the bonds and (2) takes intoaccount the expenses and sales charge associated withUnits. Since the value and estimated retirements of thebonds and the expenses of your Trust will change, there

is no assurance that the present Estimated Long-TermReturn will be realized in the future. The EstimatedCurrent Return and Estimated Long-Term Return areexpected to differ because the calculation of EstimatedLong-Term Return reflects the estimated date andamount of principal returned while the Estimated CurrentReturn calculation includes only net annual interestincome and Public Offering Price.

PUBLIC OFFERING

General. Units are offered at the Public OfferingPrice. During the initial offering period the PublicOffering Price is based on the aggregate offering priceof the bonds, the sales charge described below, cash,if any, in the Principal Account (including cash to payorganization costs) and accrued interest, if any. Themaximum sales charge for a Short-Term Trust is equalto 1.95% of the Public Offering Price per Unit (1.989%of the aggregate offering price of the bonds).Organization costs are not included in the PublicOffering Price per Unit for purposes of calculating thesales charge. After the initial public offering period, thesecondary market Public Offering Price is based onthe bid prices of the bonds, the sales chargedescribed below, cash, if any, in the Principal Accountand accrued interest, if any. The actual sales chargethat may be paid by an investor may differ slightly fromthe sales charges shown herein due to rounding thatoccurs in the calculation of the Public Offering Priceand in the number of Units purchased. The minimumpurchase in the primary and secondary market is oneUnit. Certain broker-dealers or selling firms maycharge an order handling fee for processing Unitpurchases.

The maximum secondary market sales charge iscomputed as described in the following table basedupon the estimated long-term return life in years (“ELTRLife”) of your Trust’s portfolio:

ELTR Life (Years) Sales Charge ___________________ ______________Less than 2 . . . . . . . . . . . . . . . . . . . 1.50%2 but less than 5 . . . . . . . . . . . . . . . 2.205 but less than 12 . . . . . . . . . . . . . . 2.7512 and over . . . . . . . . . . . . . . . . . . . 3.75

The ELTR Life represents the estimated life of thebonds in a Trust’s portfolio as determined for purposesof calculating Estimated Long-Term Return. See“Estimated Current and Long-Term Returns”. The sales

20

charges in the above table are expressed as apercentage of the secondary market Public OfferingPrice per Unit. For example, the maximum secondarymarket sales charge for a Trust with an ELTR Life of “5but less than 12” years would be 2.75% of the PublicOffering Price per Unit (2.828% of the aggregate bidprice of the bonds).

Reducing Your Sales Charge. The Sponsor offersways for you to reduce the sales charge that you pay. Itis your financial professional’s responsibility to alert theSponsor of any discount when you purchase Units.Before you purchase Units you must also inform yourfinancial professional of your qualification for anydiscount or a reduced sales charge.

Fee Accounts. A portion of the sales charge is waivedfor certain accounts described in this paragraph.Purchases by these accounts are subject only to a portionof the sales charge that is retained by the Sponsor. Themaximum applicable concession the Sponsor allows tobroker-dealers (either non-Underwriter or Underwriterconcession, whichever is greater) is waived. Please referto the section called “Fee Accounts” for additionalinformation on these purchases. Units may be purchasedin the initial offering period at a discount equal to thedifference between the maximum sales charge of 1.95%of the Public Offering Price per Unit and 0.60% of thePublic Offering Price per Unit for purchases by investorswho purchase Units through registered investmentadvisers, certified financial planners and registered broker-dealers who in each case either charge periodic fees forbrokerage services, financial planning, investment advisoryor asset management services, or provide such servicesin connection with the establishment of an investmentaccount for which a comprehensive “fee based” charge(“Fee Based”) is imposed (“Fee Accounts”) if the Units arepurchased for a Fee Account and the Trust is subject to aFee Based charge (i.e. the Trust is “Fee Based Eligible”).For example, with respect to a Short-Term Trust, FeeBased Eligible purchasers would pay a charge of onlyapproximately 0.60%. The Sponsor reserves the right tolimit or deny purchases of Units described in thisparagraph by investors or selling firms whose frequenttrading activity is determined to be detrimental to a Trust.

Employees. Employees, officers and directors(including their spouses (or the equivalent if recognizedunder local law) and children or step-children under 21living in the same household, parents or step-parentsand trustees, custodians or fiduciaries for the benefit of

such persons (collectively referred to herein as “relatedpurchasers”)) of Invesco Capital Markets, Inc. and itsaffiliates and, when permitted, Underwriters and theiraffiliates may purchase Units at the Public Offering Priceless the applicable underwriting commission or less theapplicable dealer concession in the absence of anunderwriting commission. Employees, officers anddirectors (including related purchasers) of dealers andtheir affiliates may purchase Units at the Public OfferingPrice less the applicable dealer concession. All employeediscounts are subject to the policies of the related sellingfirm. Only employees, officers and directors of companiesthat allow their employees to participate in this employeediscount program are eligible for the discounts.

Unit Price. The Public Offering Price of Units will varyfrom the amounts stated under “Summary of EssentialFinancial Information” in accordance with fluctuations inthe prices of the bonds. The price of Units as of theopening of business on the Date of Deposit wasdetermined by adding the applicable sales charge andorganization costs to the aggregate offering price of thebonds and dividing the sum by the number of Unitsoutstanding. This price determination was made on thebasis of an evaluation of the bonds prepared by theEvaluator using offering prices provided by a third-partypricing service. During the initial offering period, theEvaluator will value the bonds as of the Evaluation Timeon days the New York Stock Exchange is open forbusiness and will adjust the Public Offering Price of Unitsaccordingly. The “Evaluation Time” is the close of tradingon the New York Stock Exchange on each day that theExchange is open for regular trading, or earlier on dayswhere the Bond Market Association recommends an earlybond market close, provided, however, on the Date ofDeposit the Evaluation Time will be the close of regulartrading on the New York Stock Exchange or the time theregistration statement filed with the Securities andExchange Commission (the “SEC”) becomes effective, iflater. The secondary market Public Offering Price per Unitwill be equal to the aggregate bid price of the bonds plusthe applicable secondary market sales charge and dividingthe sum by the number of Units outstanding. Forsecondary market purposes, this computation will bemade by the Evaluator as of the Evaluation Time for eachday on which any Unit is tendered for redemption and asnecessary. The offering price of bonds may be expectedto range approximately from 0.125% to 1.25% more thanthe bid price. The Public Offering Price per Unit will be

21

effective for all orders received prior to the Evaluation Timeon each business day. Orders received by the Sponsorprior to the Evaluation Time and orders received byauthorized financial professionals prior to the EvaluationTime that are properly transmitted to the Sponsor by thetime designated by the Sponsor, are priced based on thedate of receipt. Orders received by the Sponsor after theEvaluation Time, and orders received by authorizedfinancial professionals after the Evaluation Time or ordersreceived by such persons that are not transmitted to theSponsor until after the time designated by the Sponsor,are priced based on the date of the next determined PublicOffering Price per Unit provided they are received timelyby the Sponsor on such date. It is the responsibility ofauthorized financial professionals to transmit ordersreceived by them to the Sponsor so they will be receivedin a timely manner.

The aggregate price of the bonds is determined on thebasis of the appropriate bid prices or offering prices, asdescribed herein, (a) on the basis of current market pricesobtained from dealers or brokers who customarily deal inbonds comparable to those held by your Trust; (b) if theseprices are not available, on the basis of current marketprices for comparable bonds; (c) by causing the value ofthe bonds to be determined by others engaged in thepractice of evaluation, quoting or appraising comparablebonds; or (d) by any combination of the above. Marketprices of the bonds will generally fluctuate with changesin market interest rates.

A person will become the owner of Units on the dateof settlement provided payment has been received. Cash,if any, made available to the Sponsor prior to the date ofsettlement for the purchase of Units may be used in theSponsor’s business and may be deemed to be a benefitto the Sponsor, subject to the limitations of the SecuritiesExchange Act of 1934, as amended (“1934 Act”).

Organization Costs. During the initial offering period,part of the Public Offering Price represents an amount ofcash deposited to pay the estimated costs incurred inestablishing your Trust. These costs include the costs ofpreparing documents relating to the Trust (such as theregistration statement, prospectus, trust agreement andlegal documents), federal and state registration fees, theinitial fees and expenses of the Trustee and the initial audit.Your Trust will reimburse us for these costs at the end ofthe initial offering period or after six months, if earlier. The

value of your Units will decline when the Trust deductsthese costs from the Trust assets.

Accrued Interest. Accrued interest is an accumulationof unpaid interest on securities which generally is paid by thebonds semi-annually, although your Trust accrues interestdaily. Because of this, your Trust always has an amount ofinterest earned but not yet collected by the Trustee. For thisreason, with respect to sales settling after the FirstSettlement Date, the proportionate share of accrued interestto the settlement date is added to the Public Offering Priceof Units. You will receive the amount of accrued interest paidon your Units on the next distribution date. In an effort toreduce the accrued interest which would have to be paid byUnitholders, the Trustee will advance the amount of accruedinterest to the Sponsor as the Unitholder of record as of theFirst Settlement Date. Consequently, the accrued interestadded to the Public Offering Price of Units will include onlyaccrued interest from the First Settlement Date to the dateof settlement, less any distributions from the Interest Accountafter the First Settlement Date. Because of the varyinginterest payment dates of the bonds, accrued interest at anypoint in time will be greater than the amount of interestactually received by your Trust and distributed to Unitholders.If you sell or redeem all or a portion of your Units, you will beentitled to receive your proportionate share of the accruedinterest from the purchaser of your Units.

Unit Distribution. Units will be distributed to thepublic by the Sponsor, other Underwriters, broker-dealersand other selling agents at the Public Offering Price, plusaccrued interest. The Sponsor intends to qualify Units forsale in a number of states.

Short-Term Trust Concessions. During the initialoffering period, the Sponsor will sell Units of the Trust tonon-Underwriter broker-dealers and selling agents at thePublic Offering Price (net of any sales charge discount)less the applicable gross concession or agencycommission of 1.10%.

Underwriters other than the Sponsor will sell Units toother broker-dealers and selling agents at the PublicOffering Price less a concession or agency commissionnot in excess of the maximum concession of 1.20%.

Financial Intermediary Transaction Concession – Abroker-dealer or other selling firm, other than anUnderwriter, purchasing Units directly from the Sponsorduring the Trust’s initial offering period as agent foranother broker-dealer or selling agent or as part of ariskless principal transaction with another broker-dealer

22

or selling agent will receive an additional concession of0.10%. The broker-dealer or selling agent receiving theconcession must have engaged the other broker-dealeror selling agent in originating the execution and notmerely be providing clearing or ministerial services.

Volume Concession Based Upon Annual Sales. Inaddition to the concessions or agency commissionsdescribed above, all broker-dealers and other sellingfirms (including Underwriters) will be eligible to receiveadditional compensation based on total initial offeringperiod sales of all eligible Invesco unit investment trustsduring the previous consecutive 12-month periodthrough the end of the most recent month. Eligible salesinclude all units of any Invesco unit investment trustunderwritten or purchased directly from Invesco duringa trust’s initial offering period. For purposes of thisconcession, trusts designated as either "Invesco UnitTrusts, Taxable Income Series" or "Invesco Unit Trusts,Municipal Series" are fixed income trusts, and trustsdesignated as "Invesco Unit Trusts Series" are equitytrusts. The Volume Concession, as applicable toInvesco fixed income and equity unit investment trusts,is set forth in the following table:

Volume Concession ____________________ Total Sales Equity Trust Fixed Income (in millions) Units Trust Units______________________ ____________ ______________

Less than $25 0.00% 0.100%$25 but less than $100 0.035% 0.100%$100 but less than $150 0.050% 0.100%$150 but less than $250 0.075% 0.100%$250 but less than $1,000 0.100% 0.100%$1,000 but less than $5,000 0.125% 0.100%$5,000 but less than $7,500 0.150% 0.100%$7,500 or more 0.175% 0.100%

Broker-dealers and other selling firms will not receivethe Volume Concession on the sale of units purchasedin Fee Accounts, however, such sales will be included indetermining whether a firm has met the sales levelbreakpoints set forth in the Volume Concession tableabove. Secondary market sales of all unit investmenttrusts are excluded for purposes of the VolumeConcession. Eligible dealer firms and other selling agentsinclude clearing firms that place orders with Invesco andprovide Invesco with information with respect to therepresentatives who initiated such transactions. Eligibledealer firms and other selling agents will not include firmsthat solely provide clearing services to other broker-

dealer firms or firms who place orders through clearingfirms that are eligible dealers. We reserve the right tochange the amount of the concessions or agencycommissions from time to time. For a trust to be eligiblefor this additional compensation, the trust’s prospectusmust include disclosure related to this additionalcompensation.

Additional Information. Certain commercial banks maybe making Units available to their customers on anagency basis. A portion of the sales charge paid by thesecustomers (equal to the concession or agencycommissions referred to above) is retained by or remittedto the banks. Any discount provided to investors will beborne by the selling dealer or agent. For secondarymarket transactions, the Sponsor will sell Units to broker-dealers and selling agents at the Public Offering Priceless a concession or agency commission of 80% of theapplicable sales charge. Dealers other than the Sponsormay sell Units in the secondary market to other broker-dealers and selling agents at the Public Offering Priceless a concession or agency commission not in excessof the secondary market concession allowed to thedealer. Notwithstanding anything to the contrary herein,in no case shall the total of any concessions, agencycommissions and any additional compensation allowedor paid to any broker, dealer or other distributor of Unitswith respect to any individual transaction exceed themaximum sales charge applicable to Short-Term Trusts.The Sponsor reserves the right to reject, in whole or inpart, any order for the purchase of Units and to changethe amount of the concession or agency commission todealers and others from time to time.

Sponsor and Underwriter Compensation. TheSponsor may sell Units to Underwriters at the regularPublic Offering Price per Unit less a gross concessiondescribed in the sections below. For a list of theUnderwriters, if any, that have purchased Units from theSponsor, see “Underwriting”.

The Sponsor will sell Units of the Trust to Underwritersat the regular Public Offering Price per Unit less theconcession of 1.35% per Unit underwritten, based on aminimum underwriting of 1,000 Units.

The concessions for (a) Units underwritten on the Dateof Deposit, (b) Units purchased from the Sponsor by anUnderwriter subsequent to the Date of Deposit during aTrust’s initial offering period, and (c) the additional per Unitconcession for Underwriters will each also be applied on

23

a dollar basis utilizing an equivalent of $1,000 per Unitand will be applied on whichever basis is more favorableto the Underwriter. Purchase orders stated in dollarswhich cannot be completely fulfilled due to therequirement that only whole Units be issued will besubject to the concession amount corresponding to thestated dollar amount of the purchase order, utilizing a$1,000 per Unit equivalent.

In addition, the Sponsor and certain Underwriters willrealize a profit or loss, as a result of the differencebetween the price paid for the bonds by the Sponsor andthe cost of the bonds to a Trust. See “Portfolio” and“Notes to Portfolio”. The Sponsor and the Underwritersmay also realize profits or losses with respect to bondswhich were acquired by the Sponsor from underwritingsyndicates of which they were members. The Sponsorhas not participated as sole underwriter or as manageror as a member of the underwriting syndicates fromwhich the bonds were acquired. Underwriters mayfurther realize profit or loss during the initial offering periodas a result of possible fluctuations in the market value ofthe bonds since all proceeds received from purchasersof Units (excluding dealer concessions or agencycommissions allowed, if any) will be retained by theUnderwriters. Affiliates of an Underwriter are entitled tothe same dealer concessions or agency commissionsthat are available to the Underwriter. In addition to anyother benefits Underwriters may realize from the sale ofUnits, the Sponsor will share with certain Underwriters aportion of any gain represented by the differencebetween the cost of the bonds to the Sponsor and theevaluation of the bonds on the Date of Deposit (lessdeductions for accrued interest and certain costs). ForUnderwriters who either (a) underwrite at least 1,000Units or (b) submit an Underwriter purchase order of atleast $1,000,000, the Sponsor will share 50% of thatportion of the gain that relates to the Units actuallyunderwritten by such Underwriters. With respect to theVolume Concession as described under “Unit Distribution– Volume Concession Based on Annual Sales,”Underwriters receive a Volume Concession of 0.100%on the Units actually underwritten. The Sponsor andcertain of the other Underwriters will also realize profitsor losses in the amount of any difference between theprice at which Units are purchased and the price at whichUnits are resold in connection with maintaining asecondary market for Units and will also realize profits or

losses resulting from a redemption of repurchased Unitsat a price above or below the purchase price.

We may provide, at our own expense and out of ourown profits, additional compensation and benefits tobroker-dealers who sell Units of the Trust and our otherproducts. This compensation is intended to result inadditional sales of our products and/or compensatebroker-dealers and financial advisors for past sales. Wemay make these payments for marketing, promotional orrelated expenses, including, but not limited to, expensesof entertaining retail customers and financial advisors,advertising, sponsorship of events or seminars, obtainingshelf space in broker-dealer firms and similar activitiesdesigned to promote the sale of the Trust and our otherproducts. Fees may include payment for travel expenses,including lodging, incurred in connection with trips takenby invited registered representatives for meetings orseminars of a business nature. These arrangements willnot change the price you pay for your Units.

Market for Units. Although not obligated to doso, the Sponsor intends to, and certain of the otherUnderwriters may, maintain a market for Units andoffer to purchase Units at prices, subject to change atany time, based upon the aggregate bid prices of thebonds plus accrued interest and any principal cash onhand, less any amounts representing taxes or othergovernmental charges payable out of your Trust andless any accrued Trust expenses. If the supply of Unitsexceeds demand or if some other business reasonwarrants it, the Sponsor and/or the Underwriters mayeither discontinue all purchases of Units or discontinuepurchases of Units at these prices. If a market is notmaintained and the Unitholder cannot find anotherpurchaser, a Unitholder will be able to dispose of Unitsby tendering them to the Trustee for redemption at theRedemption Price. See “Rights of Unitholders--Redemption of Units”. A Unitholder who wishes todispose of his Units should inquire of his broker as tocurrent market prices in order to determine whetherthere is any price in excess of the Redemption Priceand, if so, the amount thereof. The Trustee will notifythe Sponsor of any tender of Units for redemption. Ifthe Sponsor’s bid in the secondary market at that timeequals or exceeds the Redemption Price per Unit, itmay purchase the Units not later than the day onwhich the Units would otherwise have been redeemedby the Trustee.

24

FEE ACCOUNTS

As described above, Units may be available forpurchase by investors in Fee Accounts where the Trust isFee Based Eligible. You should consult your financialprofessional to determine whether you can benefit fromthese accounts. For these purchases you generally onlypay a charge of approximately 0.60%. You should consultthe “Public Offering--Reducing Your Sales Charge” sectionfor specific information on this and other sales chargediscounts. That section governs the calculation of all salescharge discounts. The Sponsor reserves the right to limitor deny purchases of Units in Fee Accounts by investorsor selling firms whose frequent trading activity isdetermined to be detrimental to a Trust.

RIGHTS OF UNITHOLDERS

Distributions of Interest and Principal. Interestreceived by a Trust, pro rated on an annual basis, will bedistributed monthly. The amount and time of the firstdistribution is described under “Summary of EssentialFinancial Information”. In addition, a Trust that has electedto be structured as a “regulated investment company” forfederal tax purposes may make additional requireddistributions at the end of each year.

Interest received by a Trust, including that part of theproceeds of any disposition of bonds which representsaccrued interest, is credited by the Trustee to the InterestAccount. Other receipts are credited to the PrincipalAccount. After deduction of amounts sufficient toreimburse the Trustee, without interest, for any amountsadvanced and paid to the Sponsor as the Unitholder ofrecord as of the First Settlement Date, interest received willbe distributed on each distribution date to Unitholders ofrecord as of the preceding record date. All distributions willbe net of estimated expenses. The Trustee is not requiredto pay interest on funds held in the Principal or InterestAccount (but may itself earn interest thereon and thereforebenefits from the use of these funds). Should the amountavailable for distribution in the Principal Account equal orexceed $5.00 per Unit, the Trustee will make a distributionfrom the Principal Account on the next monthly distributiondate to Unitholders of record on the related monthly recorddate. However, funds in the Principal Account will bedistributed on the last distribution date of each calendaryear to Unitholders of record as of the preceding recorddate if the amount available for distribution shall equal atleast $1.00 per Unit.

Because interest payments are not received by a Trustat a constant rate throughout the year, interest distributionsmay be more or less than the amount credited to theInterest Account as of the record date. For the purpose ofminimizing fluctuations in interest distributions, the Trusteeis authorized to advance amounts necessary to provideinterest distributions of approximately equal amounts. TheTrustee is reimbursed for these advances from funds in theInterest Account on the next record date. Persons whopurchase Units between a record date and a distributiondate will receive their first distribution on the seconddistribution date after the purchase.

Redemption of Units. All or a portion of your Unitsmay be tendered to The Bank of New York Mellon, theTrustee, for redemption at Unit Investment Trust Division,111 Sanders Creek Parkway, East Syracuse, New York13057, on any day the New York Stock Exchange is open.No redemption fee will be charged by the Sponsor or theTrustee, but you are responsible for applicablegovernmental charges, if any. Units redeemed by theTrustee will be canceled. You may redeem all or a portionof your Units by sending a request for redemption to yourbank or broker-dealer through which you hold your Units.No later than two business days (or any shorter period asmay be required by the applicable rules under the 1934Act) following satisfactory tender, the Unitholder will receivean amount for each Unit equal to the Redemption Priceper Unit next computed after receipt by the Trustee of thetender of Units. The “date of tender” is deemed to be thedate on which Units are received by the Trustee, exceptthat as regards Units received after the Evaluation Time ondays of trading on the New York Stock Exchange, the dateof tender is the next day on which that Exchange is openand the Units will be deemed to have been tendered tothe Trustee on that day for redemption at the RedemptionPrice. Redemption requests received by authorizedfinancial professionals prior to the Evaluation Time that areproperly transmitted to the Trustee by the time designatedby the Trustee, are priced based on the date of receipt.Redemption requests received by the Trustee after theEvaluation Time, and redemption requests received byauthorized financial professionals after the Evaluation Timeor redemption requests received by such persons that arenot transmitted to the Trustee until after the timedesignated by the Trustee, are priced based on the dateof the next determined redemption price provided they arereceived timely by the Trustee on such date. It is theresponsibility of authorized financial professionals to

25

transmit redemption requests received by them to theTrustee so they will be received in a timely manner. Certainbroker-dealers or selling firms may charge an orderhandling fee for processing redemption requests. Unitsredeemed directly through the Trustee are not subject tosuch fees.

Under Internal Revenue Service (the “IRS”) regulations,the Trustee is required to withhold a specified percentageof a Unit redemption if the Trustee has not received theUnitholder’s tax identification number as required by suchregulations or if the IRS notifies the Trustee that suchwithholding is required. Any amount withheld is transmittedto the IRS and may be recovered by the Unitholder onlywhen filing a return or a claim for refund. Under normalcircumstances the Trustee obtains the Unitholder’s taxidentification number from the selling broker. However, atany time a Unitholder elects to tender Units forredemption, the Unitholder should provide a taxidentification number to the Trustee in order to avoid thispossible “backup withholding”.

The Redemption Price per Unit (as well as thesecondary market Public Offering Price) will bedetermined on the basis of the bid price of the bonds asof the Evaluation Time on days of trading on the NewYork Stock Exchange on the date any suchdetermination is made. The Evaluator determines theRedemption Price per Unit on days Units are tenderedfor redemption. The Redemption Price per Unit is thepro rata share of each Unit on the basis of (i) the cashon hand in a Trust or moneys in the process of beingcollected, (ii) the value of the bonds based on the bidprices of the bonds, (iii) accrued interest, less (a)amounts representing taxes or other governmentalcharges and (b) the accrued Trust expenses. During theinitial offering period, the Redemption Price andsecondary market repurchase price are not reduced byestimated organization costs. The value of the bondsmay be determined by employing any of the methodsset forth in “Public Offering--Unit Price”. Accrued interestpaid on redemption shall be withdrawn from the InterestAccount or, if the balance therein is insufficient, from thePrincipal Account. All other amounts will be withdrawnfrom the Principal Account. Units so redeemed shall becancelled.

The price at which Units may be redeemed could beless than the price paid by the Unitholder and may be lessthan the par value of the bonds represented by the Units

redeemed. The Trustee may sell bonds to coverredemptions. When bonds are sold, the size and diversityof your Trust will be reduced. Sales may be required at atime when bonds would not otherwise be sold and mightresult in lower prices than might otherwise be realized.

The Trustee reserves the right to satisfy anyredemption of 1,000 or more Units with an aggregateredemption price of $1,000,000 or more in an in kinddistribution of bonds. An in kind distribution of bonds willbe made by the Trustee through the distribution of eachof the bonds in the Trust in book-entry form to theaccount of the Unitholder’s broker-dealer at DepositoryTrust Company. Amounts representing fractionalportions of a bond will be distributed in cash. TheTrustee may adjust the bonds included in a Unitholder’sin kind distribution to facilitate the distribution of wholebonds. Special tax consequences will result if aUnitholder receives an in kind distribution.

The right of redemption may be suspended andpayment postponed for any period during which the NewYork Stock Exchange is closed, other than for customaryweekend and holiday closings, or during which the SECdetermines that trading on that Exchange is restricted oran emergency exists, as a result of which disposal orevaluation of the bonds is not reasonably practicable, orfor other periods as the SEC may by order permit. Undercertain extreme circumstances the Sponsor may apply tothe SEC for an order permitting a full or partial suspensionof the right of Unitholders to redeem their Units.

Exchange Option. When you redeem Units of yourTrust or when your Trust terminates, you may be able toexchange your Units for units of other Invesco unit trusts.An exchange does not avoid a taxable disposition of yourredeemed Units. You should contact your financialprofessional for more information about trusts currentlyavailable for exchanges. Before you exchange Units, youshould read the prospectus of the new trust carefully andunderstand the risks and fees. You should then discussthis option with your financial professional to determinewhether your investment goals have changed, whethercurrent trusts suit you and to discuss tax consequences.We may discontinue this option at any time. The exchangewill generally be treated as a sale and a taxable transactionfor federal and state income tax purposes.

Units. Ownership of Units is evidenced in book-entryform only and will not be evidenced by certificates. Unitspurchased or held through your bank or broker-dealer will

26

be recorded in book-entry form and credited to theaccount of your bank or broker-dealer at the DepositoryTrust Company (“DTC”). Units are transferable bycontacting your bank or broker-dealer through which youhold your Units. Transfer, and the requirements therefore,will be governed by the applicable procedures of DTC andyour agreement with the DTC participant in whose nameyour Units are registered on the transfer records of DTC.

Reports Provided. Unitholders will receive astatement of interest and other receipts received foreach distribution. For as long as the Sponsor deems itto be in the best interest of Unitholders, the accounts ofyour Trust will be audited annually by an independentregistered public accounting firm and the report of theaccountants will be furnished to Unitholders uponrequest. Within a reasonable period of time after the endof each year, the Trustee will furnish to each person whowas a registered Unitholder during that year a statementdescribing the interest and principal received on thebonds, actual Trust distributions, Trust expenses, a listof the bonds and other Trust information. Unitholders willbe furnished the Evaluator’s evaluations of the bondsupon request to the Trustee. If you have questionsregarding your account or your Trust, please contactyour financial adviser or the Trustee. The Sponsor doesnot have access to individual account information.

TRUST ADMINISTRATION

Sponsor. Invesco Capital Markets, Inc. is theSponsor of your Trust. The Sponsor is a wholly ownedsubsidiary of Invesco Advisers, Inc. (“Invesco Advisers”).Invesco Advisers is an indirect wholly owned subsidiaryof Invesco Ltd., a leading independent global investmentmanager that provides a wide range of investmentstrategies and vehicles to its retail, institutional and highnet worth clients around the globe. The Sponsor’sprincipal office is located at 11 Greenway Plaza,Houston, Texas 77046-1173. As of June 30, 2021, thetotal stockholders’ equity of Invesco Capital Markets, Inc.was $88,006,950.61 (unaudited). The current assetsunder management and supervision by Invesco Ltd. andits affiliates were valued at approximately $1,525.0 billionas of June 30, 2021.

The Sponsor and your Trust have adopted a code ofethics requiring Invesco Ltd.’s employees who haveaccess to information on Trust transactions to reportpersonal securities transactions. The purpose of the

code is to avoid potential conflicts of interest and toprevent fraud, deception or misconduct with respect toyour Trust. The Information Supplement containsadditional information about the Sponsor. If we fail to orcannot perform our duties under the trust agreement orbecome bankrupt, the Trustee may appoint a newsponsor, continue to operate your Trust without asponsor, or terminate your Trust and distribute theliquidation proceeds.

Trustee. The Trustee is The Bank of New YorkMellon, a trust company organized under the laws ofNew York. The Bank of New York Mellon has itsprincipal unit investment trust division offices at 240Greenwich Street - 22W, New York, New York 10286,telephone (800) 856-8487. If you have questionsregarding your account or your Trust, please contactthe Trustee at its principal unit investment trust divisionoffices or your financial adviser. The Sponsor does nothave access to individual account information. TheBank of New York Mellon is subject to supervision andexamination by the Superintendent of Banks of theState of New York and the Board of Governors of theFederal Reserve System, and its deposits are insuredby the Federal Deposit Insurance Corporation to theextent permitted by law. Additional informationregarding the Trustee is set forth in the InformationSupplement, including the Trustee’s qualifications andduties, its ability to resign, the effect of a mergerinvolving the Trustee and the Sponsor’s ability to removeand replace the Trustee. See “Additional Information”.

Portfolio Administration. Your Trust is not amanaged fund and, except as provided in the TrustAgreement, bonds generally will not be sold orreplaced. The Sponsor may, however, direct that bondsbe sold in certain limited situations to protect your Trustbased on advice from the Supervisor. These situationsmay include default in interest or principal payments onthe bonds or other obligations of an issuer, anadvanced refunding or institution of certain legalproceedings. In addition, the Trustee may sell bondsdesignated by the Supervisor for purposes ofredeeming Units or payment of expenses. TheSupervisor will consider a variety of factors indesignating bonds to be sold including interest rates,market value and marketability. Except in limitedcircumstances, the Trustee must reject any offer by anissuer to issue bonds in exchange or substitution forthe bonds (such as a refunding or refinancing plan). The

27

Trustee will promptly notify Unitholders of anyexchange or substitution. The Information Supplementcontains a more detailed description of circumstancesin which bonds may be sold or replaced. See“Additional Information”.

If a Trust is structured as a “regulated investmentcompany” for federal tax purposes, the Sponsor maydirect the reinvestment of proceeds of the sale of bondsif the sale is the direct result of serious adverse creditfactors which, in the opinion of the Sponsor, would makeretention of the bonds detrimental to the Trust. In sucha case, the Sponsor may, but is not obligated to, directthe reinvestment of sale proceeds in any other securitiesthat meet the criteria for inclusion in the trust on the Dateof Deposit. The Sponsor may also instruct the Trusteeto take action necessary to ensure that such a Trustcontinues to satisfy the qualifications of a regulatedinvestment company and to avoid imposition of tax onundistributed income of the Trust.

Replacement Bonds. No assurance can be giventhat a Trust will retain its present size or compositionbecause bonds may be sold, redeemed or mature fromtime to time and the proceeds will be distributed toUnitholders and will not be reinvested. In the event of afailure to deliver any bond that has been purchased undera contract (“Failed Bonds”), the Sponsor is authorizedunder the Trust Agreement to direct the Trustee to acquireother bonds (“Replacement Bonds”) to make up theoriginal portfolio of a Trust. Replacement Bonds must bepurchased within 20 days after delivery of the notice ofthe failed contract and the purchase price (exclusive ofaccrued interest) may not exceed the amount of fundsreserved for the purchase of the Failed Bonds. TheReplacement Bonds must (i) be bonds, debentures, notesor other straight debt obligations (whether secured orunsecured and whether senior or subordinated) withoutequity or other conversion features, with fixed maturitydates substantially the same as those of the Failed Bondshaving no warrants or subscription privileges attached; (ii)be payable in United States currency; (iii) not be when, asand if issued obligations or restricted securities; and (iv)be issued or guaranteed by an issuer subject to orexempt from the reporting requirements under Section 13or 15(d) of the 1934 Act (or similar provisions of law) orguaranteed, directly or indirectly, by means of a leaseagreement, agreement to buy securities, services orproducts, or other similar commitment of the credit ofsuch an issuer to the payment of the substitute bonds.

The Trustee shall notify all Unitholders of a Trust within fivedays after the acquisition of a Replacement Bond andshall make a pro rata distribution of the amount, if any, bywhich the cost of the Failed Bond exceeded the cost ofthe Replacement Bond plus accrued interest. If FailedBonds are not replaced, the Sponsor will refund the salescharge attributable to the Failed Bonds to all Unitholdersof a Trust and distribute the principal and accrued interest(at the coupon rate of the Failed Bonds to the date ofremoval from the Trust) attributable to the Failed Bondswithin 30 calendar days after removal. If Failed Bonds arenot replaced, the Estimated Net Annual Interest Incomeper Unit would be reduced and the Estimated CurrentReturn and Estimated Long-Term Return might belowered. Unitholders may not be able to reinvest theirproceeds in other securities at a yield equal to or in excessof the yield of the Failed Bonds.

Amendment of Trust Agreement. The Sponsorand the Trustee may amend the Trust Agreement withoutthe consent of Unitholders to correct any provision whichmay be defective or to make other provisions that will notmaterially adversely affect the interest of the Unitholders(as determined in good faith by the Sponsor and theTrustee). The Trust Agreement may not be amended toincrease the number of Units or to permit the acquisitionof bonds in addition to or in substitution for any of thebonds initially deposited in a Trust, except for thesubstitution of certain refunding bonds. The Trustee willnotify Unitholders of any amendment.

Termination of Trust Agreement. A Trust willterminate upon the redemption, sale or other dispositionof the last bond held in the Trust. A Trust may also beterminated at any time by consent of Unitholders of 75%of the Units then outstanding or by the Trustee when thevalue of the Trust is less than 20% of the original principalamount of bonds. A Trust will be liquidated by the Trusteein the event that a sufficient number of Units of the Trustnot yet sold are tendered for redemption by the Sponsor,so that the net worth of the Trust would be reduced toless than 40% of the principal amount of the bonds initiallydeposited in the Trust. The Trustee will notify eachUnitholder of any termination within a reasonable time andwill then liquidate any remaining bonds. The sale of bondsupon termination may result in a lower amount than mightotherwise be realized if the sale was not required at thattime. For this reason, among others, the amount realizedby a Unitholder upon termination may be less than theprincipal amount of bonds per Unit or value at the time of

28

purchase. The Trustee will distribute to each Unitholderhis share of the balance of the Interest and PrincipalAccounts after deduction of costs, expenses orindemnities. The Unitholder will receive a final distributionstatement with this distribution. When the Trustee in itssole discretion determines that any amounts held inreserve are no longer necessary, it will distribute theseamounts to Unitholders. The Information Supplementcontains further information regarding termination of aTrust. See “Additional Information”.

Limitation on Liabilities. The Sponsor, Supervisor,Evaluator and Trustee shall be under no liability toUnitholders for taking any action or for refraining fromtaking any action in good faith pursuant to the TrustAgreement, or for errors in judgment, but shall be liableonly for their own willful misfeasance, bad faith or grossnegligence (negligence in the case of the Trustee) in theperformance of their duties or by reason of their recklessdisregard of their obligations and duties hereunder. TheTrustee shall not be liable for depreciation or loss incurredby reason of the sale by the Trustee of any of the bonds.In the event of the failure of the Sponsor to act under theTrust Agreement, the Trustee may act thereunder and shallnot be liable for any action taken by it in good faith underthe Trust Agreement. The Trustee is not liable for any taxesor governmental charges imposed on the bonds, on it asTrustee under the Trust Agreement or on a Trust which theTrustee may be required to pay under any present or futurelaw of the United States of America or of any other taxingauthority having jurisdiction. In addition, the TrustAgreement contains other customary provisions limitingthe liability of the Trustee. The Trustee and Sponsor mayrely on any evaluation furnished by the Evaluator and haveno responsibility for the accuracy thereof. Determinationsby the Evaluator shall be made in good faith upon thebasis of the best information available to it; provided,however, that the Evaluator shall be under no liability to theTrustee, Sponsor or Unitholders for errors in judgment.

FEDERAL TAX STATUS

This section summarizes some of the principal U.S.federal income tax consequences of owning Units of aTrust. Tax laws and interpretations are subject to changepossibly with retroactive effect, and this summary doesnot describe all of the tax consequences to all taxpayers.Substantial changes to the federal tax law were passedand signed into law in December 2017, many of whichbecame effective in 2018 and may affect your

investment in a Portfolio in a number of ways, includingpossible unintended consequences. Except asspecifically provided below, this summary generally doesnot describe your situation if you are a corporation, anon-U.S. person, a broker/dealer, a tax-exempt entity,financial institution, person who marks to market theirUnits or other investor with special circumstances. Inaddition, this section does not describe your alternativeminimum, state, local or foreign tax consequences.Depending on the terms of certain bond issuances,however, some of the bonds in the Trust may be exemptfrom state and local taxes of the state in which suchbonds were issued. Please consult with your tax advisorwith respect to any specific state or local taxconsequences of an investment in the Trust.

This federal income tax summary is based in part onthe advice of counsel to the Sponsor. The IRS coulddisagree with any conclusions set forth in this section.In addition, our counsel was not asked to review thefederal income tax treatment of the assets to bedeposited in the Trust. Additional information on taxesis contained in the Information Supplement.

As with any investment, you should seek advicebased on your individual circumstances from your owntax advisor.

Trust Status. The Trust intends to elect and toqualify annually as a “regulated investment company”under the federal tax laws. If the Trust qualifies as aregulated investment company and distributes itsincome as provided in the tax law, the Trust generally willnot pay federal income taxes.

Distributions. Trust distributions are generally taxableto you. After the end of each year, you will receive a taxstatement that specifies your amount of ordinary incomedistributions and capital gains dividends.

Ordinary income distributions are generally taxed atyour ordinary tax rate. Generally, you will treat all capitalgains dividends as long-term capital gains regardless ofhow long you have owned your shares. In addition, theTrust may make distributions that represent a return ofcapital for tax purposes and thus will generally not betaxable to you. The tax status of your distributions fromyour Trust is not affected by whether you reinvest yourdistributions in additional shares or receive them in cash.The income from your Trust that you must take intoaccount for federal income tax purposes is not reducedby amounts used to pay a deferred sales charge, if any.

29

The tax laws may require you to treat certain distributionsmade to you in January as if you had received them onDecember 31 of the previous year.

A distribution paid by your Trust reduces the Trust’snet asset value per Unit on the date paid by the amountof the distribution. Accordingly, a distribution paid shortlyafter a purchase of Units by a Unitholder would besubject to income tax even though it may be viewed, insubstance, as a partial return of capital.

Dividends Received Deduction and QualifiedDividend Income. A corporation that owns Unitsgenerally will not be entitled to the dividends receiveddeduction with respect to dividends received from theTrust because the dividends received deduction isgenerally not available for distributions from regulatedinvestment companies that do not invest in stock. Anindividual that owns Units generally will not be entitledto treat Trust distributions as qualified dividend incomecurrently taxed at long-term capital gains rates, as it isnot expected that Trust distributions will be attributableto qualified dividend income received by the Trust.

Sale or Redemption of Units. If you sell or redeemyour Units, you will generally recognize a taxable gain orloss. To determine the amount of this gain or loss, youmust subtract your adjusted tax basis in your Units fromthe amount you receive for the sale of the Units. Your initialtax basis in your Units is generally equal to the cost ofyour Units, generally including sales charges. In somecases, however, you may have to adjust your tax basisafter you purchase your Units.

Capital Gains and Losses. Net capital gainequals net long-term capital gain minus net short termcapital loss for the taxable year. Capital gain or loss islong term if the holding period for the asset is more thanone year and is short-term if the holding period for theasset is one year or less. You must exclude the dateyou purchase your Units to determine your holdingperiod. However, if you receive a capital gain dividendfrom your Trust and sell your Unit at a loss after holdingit for six months or less, the loss will be recharacterizedas long-term capital loss to the extent of the capital gaindividend received. The federal tax rates for capital gainsrealized from assets held for one year or less aregenerally the same as for ordinary income.

Exchanges. If you elect to have your proceedsfrom your Trust rolled over into a future series of theTrust, the exchange would generally be considered a

sale and a taxable transaction for federal income taxpurposes. In general, any gain on the sale will betreated as capital gain and any loss will be treated ascapital loss. However, any loss realized on a sale orexchange will be disallowed to the extent that Unitsdisposed of are replaced within a period of 61 daysbeginning 30 days before and ending 30 days after thedisposition of Units or to the extent that the Unitholder,during such period, acquires or enters into an optionor contract to acquire substantially identical stock orsecurities. In such a case, the basis of the Unitsacquired will be adjusted to reflect the disallowed loss.

In-Kind Distributions. Under certain circumstances,as described in this prospectus, you may receive an in-kind distribution of Trust Assets when you redeem yourUnits. In general, this distribution will be treated as a salefor federal income tax purposes and you will recognizegain or loss, based on the value at that time of thesecurities and the amount of cash received, and subjectto certain limitations on the deductibility of losses underthe tax law.

Deductibility of Trust Expenses. Expensesincurred and deducted by your Trust will generally not betreated as income taxable to you. In some cases, however,you may be required to treat your portion of these Trustexpenses as income. In these cases you may be able totake a deduction for these expenses. Recent legislation,effective in 2018, has suspended the deductibility ofexpenses that are characterized as miscellaneous itemizeddeductions, such as investment expenses.

Foreign Investors. If you are a foreign investor (i.e.,an investor other than a U.S. citizen or resident or a U.S.corporation, partnership, estate or trust), you should beaware that, generally, subject to applicable tax treaties,distributions from the Trust will be characterized asdividends for federal income tax purposes (other thandividends which the Trust reports as capital gaindividends) and will generally be subject to U.S. incometaxes, including withholding taxes, subject to certainexceptions. However distributions received by a foreigninvestor from the Trust that are properly reported by theTrust as capital gain dividends may not be subject to U.S.federal income taxes, including withholding taxes,provided that the Trust makes certain elections andcertain other conditions are met. Distributions received bya foreign investor attributable to interest-related dividendsof a regulated investment company such as the Trust may

30

not be subject to U.S. federal income tax withholding. Theamount of distributions that may be reported as interest-related dividends will be limited to the amount of qualifiednet interest income, which is generally the Trust’s U.S.-source interest income less allocable expenses.

The Foreign Account Tax Compliance Act(“FATCA”). A 30% withholding tax on your Trust’sdistributions, including capital gains distributions generallyapplies if paid to a foreign entity unless: (i) if the foreignentity is a “foreign financial institution” as defined underFATCA, the foreign entity undertakes certain due diligence,reporting, withholding, and certification obligations, (ii) if theforeign entity is not a “foreign financial institution,” itidentifies certain of its U.S. investors or (iii) the foreign entityis otherwise excepted under FATCA. If required under therules above and subject to the applicability of anyintergovernmental agreements between the United Statesand the relevant foreign country, withholding under FATCAmay apply. Under existing regulations, FATCA withholdingon gross proceeds from the sale of Units and capital gaindistributions from your Portfolio took effect on January 1,2019; however, recently proposed U.S. tax regulations, iffinalized in their proposed form, would eliminate FATCAwithholding on such types of payments. If withholding isrequired under FATCA on a payment related to your Units,investors that otherwise would not be subject towithholding (or that otherwise would be entitled to areduced rate of withholding) on such payment generallywill be required to seek a refund or credit from the IRS toobtain the benefit of such exemption or reduction. YourTrust will not pay any additional amounts in respect ofamounts withheld under FATCA. You should consult yourtax advisor regarding the effect of FATCA based on yourindividual circumstances.

Backup Withholding. By law, your Trust mustwithhold as backup withholding a percentage (currently24%) of your taxable distributions and redemptionproceeds if you do not provide your correct socialsecurity or taxpayer identification number and certify thatyou are not subject to backup withholding, or if the IRSinstructs your Trust to do so.

Investors Should Consult Their Tax Advisors.Investors in the Trust may be subject to federal, state,local, or foreign taxes in connection with their investmentin the Trust. Investors are encouraged to consult their owntax advisors regarding the specific federal, state, local,

and foreign tax consequences that may affect them as aresult of an investment in the Trust.

EXPENSES

General. The Trustee will periodically deduct from theInterest Account and, to the extent funds are not sufficienttherein, from the Principal Account, amounts necessaryto pay the expenses of the Trust, provided thatorganization costs are generally paid out of cashdeposited in the Principal Account. The Trustee also maywithdraw from these Accounts such amounts, if any, as itdeems necessary to establish a reserve for anygovernmental charges payable out of the Trust. Amountsso withdrawn shall not be considered a part of a Trust’sassets until such time as the Trustee shall return all or anypart of such amounts to the appropriate Accounts.

Organization Costs. You and the otherUnitholders will bear all or a portion of the organizationcosts and charges incurred in connection with theestablishment of your Trust. These costs and chargeswill include the cost of the preparation, printing andexecution of the trust agreement, registrationstatement and other documents relating to your Trust,federal and state registration fees and costs, the initialfees and expenses of the Trustee, and legal andauditing expenses. The Public Offering Price of Unitsincludes the estimated amount of these costs. TheTrustee will deduct these expenses from your Trust’sassets at the end of the initial offering period or aftersix months, if earlier.

Sponsor, Supervisor, Evaluator and Trustee.The Sponsor and the Supervisor, which is an affiliate ofthe Sponsor, will receive the annual fee indicated under“Summary of Essential Financial Information” forproviding bookkeeping and administrative services andfor providing portfolio supervisory services for the Trust.These fees may exceed the actual costs of providingthese services for the Trust but the total amountreceived for providing these services to all Invesco unitinvestment trusts will not exceed the total cost ofproviding the services in any calendar year. TheEvaluator, which is an affiliate of the Sponsor, willreceive the annual evaluation fee indicated under“Summary of Essential Financial Information” forevaluating the Trust’s portfolio. This fee may exceed theactual costs of providing these services for the Trustbut the total amount received for providing evaluations

31

services to all Invesco unit investment trusts will notexceed the total cost of providing the services in anycalendar year. For its services the Trustee will receivethe fee indicated under “Summary of Essential FinancialInformation” (which may be reduced as describedtherein). Part of the Trustee’s compensation for itsservices is expected to result from the use of the fundsbeing held in the Principal and Interest Accounts forfuture distributions, payment of expenses andredemptions since these Accounts are non-interestbearing to Unitholders. These fees are based on theoutstanding principal amount of bonds and Units onthe Date of Deposit for the first year and as of the closeof business on January 1 for each year thereafter. TheSponsor’s, Supervisor’s, Evaluator’s and Trustee’s feesmay be increased without approval of the Unitholdersby amounts not exceeding proportionate increasesunder the category “Services Less Rent of Shelter” inthe Consumer Price Index for All Urban Consumers or,if this category is not published, in a comparablecategory.

Miscellaneous Expenses. The following additionalcharges are or may be incurred by the Trust: (a) fees ofthe Trustee for extraordinary services, (b) expenses of theTrustee (including legal and auditing expenses) and ofcounsel designated by the Sponsor, (c) variousgovernmental charges, (d) expenses and costs of anyaction taken by the Trustee to protect the Trust and therights and interests of Unitholders, (e) indemnification ofthe Trustee for any loss, liability or expenses incurred byit in the administration of the Trust without negligence, badfaith or willful misconduct on its part, (f) any specialcustodial fees payable in connection with the sale of anyof the bonds in the Trust, (g) expenditures incurred incontacting Unitholders upon termination of the Trust and(h) costs incurred to reimburse the Trustee for advancingfunds to the Trust to meet scheduled distributions (whichcosts may be adjusted periodically in response tofluctuations in short-term interest rates). The Trust will paythe costs associated with updating its registrationstatement each year. The fees and expenses set forthherein are payable out of the Trust. When such fees andexpenses are paid by or owing to the Trustee, they aresecured by a lien on the portfolio of the Trust. If thebalances in the Interest and Principal Accounts areinsufficient to provide for amounts payable by the Trust,the Trustee has the power to sell bonds to pay suchamounts.

ADDITIONAL INFORMATION

This prospectus does not contain all the informationset forth in the registration statements filed by your Trustwith the SEC under the Securities Act of 1933 and theInvestment Company Act of 1940 (file no. 811-02754).The Information Supplement, which has been filed withthe SEC, includes more detailed information concerningthe bonds in your Trust, investment risks and generalinformation about the Trust. Reports and other informationabout your Trust are available on the EDGAR Databaseon the SEC’s Internet site at http://www.sec.gov. Copiesof this information may be obtained, after paying aduplication fee, by electronic request at the following e-mail address: publicinfo@sec.gov.

OTHER MATTERS

Legal Matters. The legality of the Units offeredhereby and certain matters relating to federal tax lawhave been passed upon by Morgan, Lewis & BockiusLLP. Dorsey & Whitney LLP has acted as counsel to theTrustee.

Independent Registered Public AccountingFirm. The financial statements included in thisprospectus have been so included in reliance upon thereport of Grant Thornton LLP, independent registeredpublic accountants, upon the authority of said firm asexperts in accounting and auditing.

32

THIS PAGE INTENTIONALLY LEFT BLANK.

THIS PAGE INTENTIONALLY LEFT BLANK.

THIS PAGE INTENTIONALLY LEFT BLANK.

➢ Contents of Prospectus Investment Objective................................................2 Principal Investment Strategy...................................2 Principal Risks .........................................................2 Summary of Essential Financial Information..............3 Portfolio ...................................................................4 Notes to Portfolio.....................................................6 Underwriting ............................................................6 Report of Independent Registered Public Accounting Firm.........................................7 Statement of Condition ............................................8 The Trust..................................................................9 Estimated Current and Long-Term Returns ............20 Public Offering .......................................................20 Fee Accounts.........................................................25 Rights of Unitholders..............................................25 Trust Administration ...............................................27 Federal Tax Status .................................................29 Expenses...............................................................31 Additional Information ............................................32 Other Matters ........................................................32

➢ Daily Prices ◊ Call our 24-Hour Pricing Line (800) 953-6785 ◊ Visit our Unit Trusts Daily Pricing Page http://www.invesco.com/UIT

➢ Account Questions ◊ Contact the Trustee (800) 856-8487

➢ Learning More About Unit Trusts ◊ Contact Invesco (630) 684-6000 ◊ Visit our Unit Trusts Internet Page http://www.invesco.com/UIT

➢ Additional Information You may obtain an Information Supplement that provides more details about your trust and its policies. ◊ Visit the SEC Internet Site http://www.sec.gov ◊ Contact the Trustee (800) 856-8487______________When Units of the Trust are no longer available this prospectus maybe used as a preliminary prospectus for a future Trust. If thisprospectus is used for future Trusts you should note the following:

The information in this prospectus is not complete with respect tofuture Trust series and may be changed. No person may sell Unitsof future Trusts until a registration statement is filed with theSecurities and Exchange Commission and is effective. Thisprospectus is not an offer to sell Units and is not soliciting an offerto buy Units in any state where the offer or sale is not permitted.

U-IGSCPRO34U-TISPRO637

PROSPECTUS

October 7, 2021

Taxable Income Series 637

Investment Grade CorporateTrust, 3-7 Year Series 34