Form 497K FEDERATED INCOME SECURIT

The information contained herein relates to all classes of the Fund's Shares, as listed below, unless otherwise noted.

Share Class | Ticker

A | FUSGX

B | FUSBX

C | FUSCX

Federated Fund for U.S. Government Securities

A Portfolio of Federated Income Securities Trust

Before you invest, you may want to review the Fund's Prospectus, which contains more information about the Fund and its risks. You can find the Fund's Prospectus and other information about the Fund, including the Statement of Additional Information and most recent reports to shareholders, online at FederatedInvestors.com/FundInformation. You can also get this information at no cost by calling 1-800-341-7400 or by sending an email request to [email protected] or from a financial intermediary through which Shares of the Fund may be bought or sold. The Fund's Prospectus and Statement of Additional Information, both dated May 31, 2018, are incorporated by reference into this Summary Prospectus.

A mutual fund seeking to provide current income by investing primarily in a diversified portfolio of U.S. government securities, including mortgage-backed securities of investment-grade quality.

As with all mutual funds, the Securities and Exchange Commission (SEC) has not approved or disapproved these securities or passed upon the adequacy of this Prospectus. Any representation to the contrary is a criminal offense.

Not FDIC Insured ■ May Lose Value ■ No Bank Guarantee

Fund Summary Information

Federated Fund for U.S. Government Securities (the “Fund”)

RISK/RETURN SUMMARY: INVESTMENT OBJECTIVE

The Fund's investment objective is to provide current income.

RISK/RETURN SUMMARY: FEES AND EXPENSES

This table describes the fees and expenses that you may pay if you buy and hold the Class A Shares (A), Class B Shares (B) or Class C Shares (C) of the Fund. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000, in certain classes (e.g., A class) of Federated funds. More information about these and other discounts is available from your financial professional, in the “What Do Shares Cost?” section of the Prospectus on page 12 and in “Appendix B” to this Prospectus.

Shareholder Fees (fees paid directly from your investment)	A	B	C
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	4.50%	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of original purchase price or redemption proceeds, as applicable)	0.00%	5.50%	1.00%
Maximum Sales Charge (Load) Imposed on Reinvested Dividends (and other Distributions) (as a percentage of offering price)	None	None	None
Redemption Fee (as a percentage of amount redeemed, if applicable)	None	None	None
Exchange Fee	None	None	None
Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Management Fee	0.40%	0.40%	0.40%
Distribution (12b-1) Fee	None	0.75%	0.75%
Other Expenses	0.57%	0.57%	0.57%
Total Annual Fund Operating Expenses	0.97%	1.72%	1.72%

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Example

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.

The Example assumes that you invest $10,000 for the time periods indicated and then redeem all of your Shares at the end of those periods. Expenses assuming no redemption are also shown. The Example also assumes that your investment has a 5% return each year and that operating expenses are as shown in the table above and remain the same. Although your actual costs and returns may be higher or lower, based on these assumptions your costs would be:

Share Class	1 Year	3 Years	5 Years	10 Years
A:
Expenses assuming redemption	$545	$745	$962	$1,586
Expenses assuming no redemption	$545	$745	$962	$1,586
B:
Expenses assuming redemption	$725	$942	$1,133	$1,831
Expenses assuming no redemption	$175	$542	$933	$1,831
C:
Expenses assuming redemption	$275	$542	$933	$2,030
Expenses assuming no redemption	$175	$542	$933	$2,030

Portfolio Turnover

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund Shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 45% of the average value of its portfolio.

RISK/RETURN SUMMARY: INVESTMENTS, RISKS and PERFORMANCE

What are the Fund's Main Investment Strategies?

The Fund seeks to provide current income. Under normal market conditions, the Fund invests primarily in a diversified portfolio of U.S government securities, including mortgage-backed securities (MBS) of investment-grade quality, and seeks to provide returns consistent with investments in the market for U.S. home mortgages. The Fund will invest in MBS that are issued or guaranteed by U.S. government agencies or U.S. government-sponsored enterprises (GSEs). The Fund may invest in non-agency MBS, which are those not issued or guaranteed by GSEs. The Fund also may invest in asset-backed securities, other U.S. government securities and certain derivative instruments.

The Fund typically seeks to maintain an overall average dollar-weighted portfolio duration that is within 20% above or below the Bloomberg Barclays US Mortgage-Backed Securities Index (the “Index”). At times, the Adviser's calculation of portfolio duration may result in variances outside this range.

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Duration is a measure of the price volatility of a fixed-income security as a result of changes in market rates of interest, based on the weighted average timing of the instrument's expected fixed interest and principal payments. The Adviser seeks to create a portfolio, consisting of MBS, derivative instruments and other securities, that outperforms the Index.

Based on fundamental analysis, the Adviser will consider a variety of factors when making decisions to purchase or sell particular securities or derivative contracts. The Fund may, but is not required to, use derivative instruments, which are instruments that have a value based on another instrument, exchange rate or index, and may be used as substitutes for securities in which the Fund can invest, or to hedge against a potential loss in the underlying asset. There can be no assurance that the Fund's use of derivative instruments will work as intended.

The Fund will invest its assets so that at least 80% of its net assets (plus any borrowings for investment purposes) are invested in U.S. government securities. The Fund will notify shareholders at least 60 days in advance of any change in its investment policy that would enable the Fund to invest, under normal circumstances, less than 80% of its net assets (plus any borrowings for investment purposes) in U.S. government securities.

WHAT ARE THE MAIN RISKS OF INVESTING IN THE FUND?

All mutual funds take investment risks. Therefore, it is possible to lose money by investing in the Fund. The primary factors that may reduce the Fund's returns include:

■	MBS Risk. A rise in interest rates may cause the value of MBS held by the Fund to decline. Certain MBS issued by GSEs are not backed by the full faith and credit of the U.S. government. A non-agency MBS is subject to the risk that the value of such security will decline, because the security is not issued or guaranteed as to principal or interest by the U.S. government or a GSE. The Fund's investments in collateralized mortgage obligations (CMOs) may entail greater market, prepayment and liquidity risks than other MBS.
■	Asset-Backed Securities (ABS) Risk. The value of asset-backed securities (ABS) may be affected by certain factors such as interest rate risk, credit risk, prepayment risk and the availability of information concerning the pool of underlying assets and its structure. Under certain market conditions, ABS may be less liquid and may be difficult to value. Movements in interest rates (both increases and decreases) may quickly and significantly reduce the value of certain types of ABS. ABS can also be subject to the risk of default on the underlying assets.
■	Interest Rate Risk. Prices of fixed-income securities generally fall when interest rates rise. The longer the duration of a fixed-income security, the more susceptible it is to interest-rate risk. Recent and potential future changes in monetary policy made by central banks and/or their governments are likely to affect the level of interest rates.

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■	Credit Risk. It is possible that borrowers of non-agency MBS in which the Fund invests will fail to pay interest or principal on these securities when due, which would result in the Fund losing money.
■	Counterparty Risk. Counterparty risk includes the possibility that a party to a transaction involving the Fund will fail to meet its obligations. This could cause the Fund to lose money or to lose the benefit of the transaction or prevent the Fund from selling or buying other securities to implement its investment strategy.
■	Prepayment Risk. When homeowners prepay their mortgages in response to lower interest rates, the Fund will be required to reinvest the proceeds at the lower interest rates available. Also, when interest rates fall, the prices of MBS may not rise to as great an extent as those of other fixed-income securities due to the potential prepayment of higher interest mortgages.
■	Risk of Security Downgrades. The downgrade of the credit of a security held by the Fund may decrease its value. Fixed-income securities with lower ratings tend to have a higher probability that a borrower will default or fail to meet its payment obligations.
■	Liquidity Risk. The non-agency MBS and CMOs in which the Fund invests may be less readily marketable and may be subject to greater fluctuation in price than other securities.
■	Leverage Risk. Leverage risk is created when an investment exposes the Fund to a level of risk that exceeds the amount invested. Changes in the value of such an investment magnify the Fund's risk of loss and potential for gain.
■	Risk of Investing in Derivative Instruments. The Fund's exposure to derivative contracts (either directly or through its investment in another investment company) involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. The use of derivatives can lead to losses because of adverse movements in the price or value of the asset, index, rate or instrument underlying a derivative, due to failure of a counterparty, or the failure of the counterparty to meet its obligations under the contract, or due to tax or regulatory constraints. Derivatives may create investment leverage in the Fund, which magnifies the Fund's exposure to the underlying investment. Derivative instruments may be difficult to value, may be illiquid and may be subject to wide swings in valuation caused by changes in the value of the underlying instrument. Over-the-counter derivative contracts generally carry greater liquidity risk than exchange-traded contracts. The loss on derivative transactions may substantially exceed the initial investment.
■	Asset Segregation Risk. The requirement to secure its obligations in connection with certain transactions, including derivatives or other transactions that expose it to an obligation of another party, by owning underlying assets, entering into offsetting transactions or setting aside cash or liquid assets, may cause the Fund to miss favorable trading opportunities, or to realize losses on such offsetting transactions.

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Risk Related to the Economy. The value of the Fund's portfolio may decline in tandem with a drop in the overall value of the markets in which the Fund invests and/or other markets. Economic, political and financial conditions may, from time to time, and for varying periods of time, cause the Fund to experience volatility, illiquidity, shareholder redemptions, or other potentially adverse effects. Among other investments, lower-grade bonds may be particularly sensitive to changes in the economy.

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Technology Risk. The Adviser uses various technologies in managing the Fund, consistent with its investment objective and strategy described in this Prospectus. For example, proprietary and third party data and systems are utilized to support decision making for the Fund. Data imprecision, software or other technology malfunctions, programming inaccuracies and similar circumstances may impair the performance of these systems, which may negatively affect Fund performance.

The Shares offered by this Prospectus are not deposits or obligations of any bank, are not endorsed or guaranteed by any bank and are not insured or guaranteed by the U.S. government, the Federal Deposit Insurance Corporation, the Federal Reserve Board or any other government agency.

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Performance: Bar Chart and Table

Risk/Return Bar Chart

The bar chart and performance table below reflect historical performance data for the Fund and are intended to help you analyze the Fund's investment risks in light of its historical returns. The bar chart shows the variability of the Fund's A class total returns on a calendar year-by-year basis. The Average Annual Total Return table shows returns for each class averaged over the stated periods, and includes comparative performance information. The Fund's performance will fluctuate, and past performance (before and after taxes) is not necessarily an indication of future results. Updated performance information for the Fund is available under the “Products” section at FederatedInvestors.com or by calling 1-800-341-7400.

The total returns shown in the bar chart for the Fund's A class do not reflect the payment of any sales charges or recurring shareholder account fees. If these charges or fees had been included, the returns shown would have been lower.

The Fund's A class total return for the three-month period from January 1, 2018 to March 31, 2018, was (1.21)%.

Within the periods shown in the bar chart, the Fund's A class highest quarterly return was 2.48% (quarter ended March 31, 2009). Its lowest quarterly return was (2.21)% (quarter ended June 30, 2013).

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Average Annual Total Return Table

In addition to Return Before Taxes, Return After Taxes is shown for the Fund's A class to illustrate the effect of federal taxes on Fund returns. After-tax returns are shown only for the A class, and after-tax returns for the B class and C class will differ from those shown for the A class. Actual after-tax returns depend on each investor's personal tax situation, and are likely to differ from those shown. After-tax returns are calculated using a standard set of assumptions. The stated returns assume the highest historical federal income and capital gains tax rates. These after-tax returns do not reflect the effect of any applicable state and local taxes. After-tax returns are not relevant to investors holding Shares through tax-deferred programs, such as a 401(k) plan, an Individual Retirement Account or other tax-advantaged investment plans.

(For the Period Ended December 31, 2017)

Share Class	1 Year	5 Years	10 Years
A:
Return Before Taxes	(2.95)%	0.41%	2.33%
Return After Taxes on Distributions	(3.92)%	(0.68)%	1.06%
Return After Taxes on Distributions and Sale of Fund Shares	(1.67)%	(0.19)%	1.28%
B:
Return Before Taxes	(4.46)%	0.23%	2.17%
C:
Return Before Taxes	(0.12)%	0.61%	2.03%
Bloomberg Barclays U.S. Mortgage Backed Securities Index1 (reflects no deduction for fees, expenses or taxes)	2.47%	2.04%	3.84%
Lipper U.S. Mortgage Funds Average2	2.84%	1.96%	3.68%

1	The Bloomberg Barclays U.S. Mortgage Backed Securities Index tracks agency mortgage-backed pass-through securities (both fixed-rate and hybrid ARM) guaranteed by Ginnie Mae (GNMA), Fannie Mae (FNMA) and Freddie Mac (FHLMC).
2	Lipper figures represent the average of the total returns reported by all of the mutual funds designated by Lipper, Inc. as falling in the respective category indicated and is not adjusted to reflect any sales charges.

FUND MANAGEMENT

The Fund's Investment Adviser is Federated Investment Management Company.

Todd A. Abraham, CFA, Senior Vice President of the Adviser, has been the Fund's portfolio manager since May 2003.

Liam O'Connell, CFA, Portfolio Manager, has been the Fund's portfolio manager since May 2017.

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purchase and sale of fund shares

Class B Shares are closed to new investments by new investors and existing shareholders (excluding reinvestment of dividends and capital gains). Reinvestment of dividends and capital gains will continue uninterrupted. Effective February 1, 2018, exchanges of Class B Shares were only permitted into Class B Shares of Federated Government Reserves Fund. Effective June 18, 2018, Class B Shares of the Fund may be exchanged for Class B Shares of any other Federated fund.

Please disregard any further references to purchases of Class B Shares with the exception of Class B Share exchanges.

You may purchase, redeem or exchange Shares of the Fund on any day the New York Stock Exchange is open. Shares may be purchased through a financial intermediary firm that has entered into a Fund selling and/or servicing agreement with the Distributor or an affiliate (“Financial Intermediary”) or directly from the Fund, by wire or by check. Please note that certain purchase restrictions may apply. Redeem or exchange Shares through a financial intermediary or directly from the Fund by telephone at 1-800-341-7400 or by mail.

The minimum investment amount for the Fund's A class, B class and C class is generally $1,500 for initial investments and $100 for subsequent investments. The minimum initial and subsequent investment amounts for Individual Retirement Accounts (IRAs) are generally $250 and $100, respectively. Certain types of accounts are eligible for lower minimum investments. The minimum investment for Systematic Investment Programs is $50.

Tax Information

The Fund's distributions are taxable as ordinary income or capital gains except when your investment is through a 401(k) plan, an Individual Retirement Account or other tax-advantaged investment plan.

Payments to Broker-Dealers and Other Financial Intermediaries

If you purchase the Fund through a broker-dealer or other financial intermediary (such as a bank), the Fund and/or its related companies may pay the intermediary for the sale of Fund Shares and related services. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your financial intermediary's website for more information.

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Federated Fund for U.S. Government Securities
Federated Investors Funds
4000 Ericsson Drive
Warrendale, PA 15086-7561

Contact us at FederatedInvestors.com
or call 1-800-341-7400.

Federated Securities Corp., Distributor

Investment Company Act File No. 811-4577

CUSIP 31420C704
CUSIP 31420C803
CUSIP 31420C886

Q450294 (5/18)

Federated is a registered trademark of Federated Investors, Inc.
2018 ©Federated Investors, Inc.