Tax Exempt Municipal Income Trust, Series 340
Ticker Symbol: FMOMMX

Estimated organization costs will be deducted from the assets of the trust at the end of the initial offering period.

Estimated organization costs and trust operating expenses are assessed on a fixed dollar amount per unit basis. Actual expenses may be more or less than the estimates.

*Weighted average maturity represents the average amount of time remaining until the bonds held in the trust mature, taking into account each bond’s weight within the portfolio based on its market value.

**Estimated current return is calculated by dividing estimated net annual interest income per unit by the public offering price. Estimated long-term return is calculated using a formula which (1) factors in the relative weightings of the market values, yields and estimated retirements of the securities; and (2) takes into account a compounding factor, the sales charge and expenses. There is no assurance that the returns will be realized in the future because the various components used to calculate these figures will change. In addition, neither rate reflects the true return you will receive, which will be lower, because neither includes the effect of certain delays in distributions with respect to when the securities pay interest and when distributions are paid by the trust.

***The taxable equivalent estimated current return is for illustrative purposes only. This information illustrates approximately what you would have to earn on taxable investments to equal the tax-exempt estimated current return using the highest federal tax bracket and Medicare tax for 2025. This information is based on present law as of the date of publication and does not account for any proposed changes in tax rates. This information does not account for limitations on deductions, the alternative minimum tax or taxes other than Federal personal income tax.

Distributions

This unit investment trust seeks to distribute monthly income.

Distributions, if any, are paid on the twenty-fifth day of each month to unit holders of record on the tenth day of each month with the initial distribution per unit scheduled to occur on May 25, 2025 and estimated regular distributions per unit scheduled to begin on June 25, 2025. The actual distribution you receive will vary from that set forth above with changes in the portfolio’s fees and expenses and with the sale, maturity or redemption of securities.

You should consider the portfolio's investment objectives, risks, and charges and expenses carefully before investing. Contact your financial professional or call First Trust Portfolios L.P. at 1.800.621.1675 to request a prospectus, which contains this and other information about the portfolio. Read it carefully before you invest.

Risk Considerations
An investment in this unmanaged unit investment trust should be made with an understanding of the risks associated with an investment in municipal bonds. Municipal bonds are subject to numerous risks including rising interest rates, economic recession, deterioration of the municipal bond market, possible downgrades, increased volatility, reduced liquidity and defaults of interest and/or principal.

Certain of the securities in the trust are covered by insurance policies obtained by the issuers or underwriters of the bond from insurance companies. There can be no assurance that any insurer will be able to satisfy its commitments in the event claims are made in the future.

This UIT is a buy and hold strategy and investors should consider their ability to hold the trust until maturity.

The value of the securities held by the trust may be subject to steep declines or increased volatility due to changes in performance or perception of the issuers. The markets for credit instruments, including municipal securities, have experienced periods of extreme illiquidity and volatility.

As the use of Internet technology has become more prevalent in the course of business, the trust has become more susceptible to potential operational risks through breaches in cybersecurity.

Ongoing armed conflicts between Russia and Ukraine in Europe and among Israel, Hamas and other militant groups in the Middle East, have caused and could continue to cause significant market disruptions and volatility within the markets in Russia, Europe, the Middle East and the United States. The hostilities and sanctions resulting from those hostilities could have a significant impact on certain investments as well as performance.

A public health crisis, and the ensuing policies enacted by governments and central banks in response, could cause significant volatility and uncertainty in global financial markets, negatively impacting global growth prospects.