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<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;"><b>
Investment Goal
</b></p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">The Fund's investment objective is above-average total return through a combination of current income and capital appreciation.</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;"><b>
Fund Fees & Expenses
</b></p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">The following table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. You may qualify for a sales charge discount if you invest at least $250,000 in the Fund. More information about this and other discounts is available from your financial professional and in the section "How Sales Charges Are Calculated" on page 74 of the Prospectus and on page 104 in the section "Reduced Sales Charges" of the Statement of Additional Information ("SAI").</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;"><b>
Shareholder Fees </b></p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;"><b>
(fees paid directly from your investment)</b></p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;"><b>
Annual Fund Operating Expenses
</b></p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;"><b>
(expenses that you pay each year as a percentage of the value of your investment) </b></p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;"><b>
Example
</b></p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">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 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods (except where indicated). The example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same, except that the example is based on the Total Annual Fund Operating Expenses After Fee Waiver and/or Expense Reimbursement assuming that such waiver and/or reimbursement will only be in place through the date noted above and on the Total Annual Fund Operating Expenses for the remaining periods. Although your actual costs may be higher or lower, based on these assumptions your costs would be:</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;"><b>
Portfolio Turnover
</b></p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">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 for you if your 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 its most recently ended fiscal year, the Fund's portfolio turnover rate was 151% of the average value of its portfolio.</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;"><b>
Investments, Risks and Performance
</b></p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;"><b>
Principal Investment Strategies
</b></p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">Under normal circumstances, the Fund will invest at least 80% of its net assets (plus any borrowings made for investment purposes) in fixed-income securities (for example, bonds and other investments that Loomis Sayles believes have similar economic characteristics, such as notes, debentures and loans). It is anticipated that the Fund's weighted average duration will generally be between two and five years. Duration is a measure of the expected life of a fixed-income security that is used to determine the sensitivity of a security's price to changes in interest rates. A fund with a longer average portfolio duration will be more sensitive to changes in interest rates than a fund with a shorter average portfolio duration. By way of example, the price of a bond fund with an average duration of five years would be expected to fall approximately 5% if interest rates rose by one percentage point.</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">The Fund will purchase only investment-grade fixed-income securities, which are those securities that are rated in one of the top four rating categories at the time of purchase by at least one of the three major ratings agencies (Moody's Investors Service, Inc., Fitch Investor Services, Inc. or S&P Global Ratings) or, if unrated, are determined by Loomis Sayles to be of comparable quality. The Fund may continue to hold up to 10% of its net assets in securities that are downgraded to a rating below investment-grade subsequent to their purchase if Loomis Sayles believes it is appropriate to do so.</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">In deciding which securities to buy and sell, Loomis Sayles may consider a number of factors related to the bond issue and the current bond market, for example, including, the stability and volatility of a country's bond markets, the financial strength of the issuer, current interest rates, current valuations, Loomis Sayles' expectations regarding general trends in interest rates and currency considerations. Loomis Sayles will also consider how purchasing or selling a bond would impact the overall portfolio's risk profile (for example, its sensitivity to currency risk, interest rate risk and sector-specific risk) and potential return (income and capital gains).</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">Three themes typically drive the Fund's investment approach. First, Loomis Sayles generally seeks fixed-income securities that are attractively valued relative to the Loomis Sayles' credit research team's assessment of credit risk. The broad coverage combined with the objective of identifying attractive investment opportunities makes this an important component of the investment approach. Second, the Fund may invest significantly in securities the prices of which Loomis Sayles believes are more sensitive to events related to the underlying issuer than to changes in general interest rates or overall market default rates. These securities may not have a direct correlation with changes in interest rates, thus helping to manage interest rate risk and to offer diversified sources for return. Third, Loomis Sayles analyzes different sectors of the economy and differences in the yields ("spreads") of various fixed-income securities in an effort to find securities that it believes may produce attractive returns for the Fund in comparison to their risk.</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">The Fund may invest up to 20% of its assets in U.S. dollar-denominated foreign securities, including emerging market securities. The Fund may invest without limit in obligations of supranational entities (e.g., the World Bank). Although certain securities purchased by the Fund may be issued by domestic companies incorporated outside of the United States, the Adviser does not consider these securities to be foreign if the issuer is included in the U.S. fixed-income indices published by Bloomberg Barclays. The Fund may also invest in mortgage-related securities, including mortgage dollar rolls. The Fund may also engage in futures transactions for hedging and investment purposes.</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">The fixed-income securities in which the Fund may invest include, among other things, corporate bond and other debt securities (including junior and senior bonds), U.S. government securities, zero-coupon securities, mortgage-backed securities and other asset-backed securities, real estate investment trusts ("REITs") and securities issued pursuant to Rule 144A under the Securities Act of 1933 ("Rule 144A securities").</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">The Fund may also engage in active and frequent trading of securities. Frequent trading may produce a high level of taxable gains, including short-term capital gains taxable as ordinary income, as well as increased trading costs, which may lower the Fund's return.</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;"><b>
Principal Investment Risks
</b></p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">The principal risks of investing in the Fund are summarized below. The Fund does not represent a complete investment program. You may lose money by investing in the Fund.</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">
<b>Below Investment Grade Fixed-Income Securities Risk:</b> The Fund's investments in below investment grade fixed-income securities, also known as "junk bonds," may be subject to greater risks than other fixed-income securities, including being subject to greater levels of interest rate risk, credit/counterparty risk (including a greater risk of default) and liquidity risk. The ability of the issuer to make principal and interest payments is predominantly speculative for below investment grade fixed-income securities.</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">
<b>Credit/Counterparty Risk:</b> Credit/counterparty risk is the risk that the issuer or guarantor of a fixed-income security, or the counterparty to a derivatives or other transaction, will be unable or unwilling to make timely payments of interest or principal or to otherwise honor its obligations. The Fund will be subject to credit risks with respect to the counterparties of its derivatives transactions. Many of the protections afforded to participants on organized exchanges, such as the performance guarantee of an exchange clearing house, are not available in connection with over-the-counter ("OTC") derivatives transactions, such as foreign currency transactions. As a result, in instances when the Fund enters into OTC derivatives transactions, the Fund will be subject to the risk that its counterparties will not perform their obligations under the transactions and that the Fund will sustain losses or be unable to realize gains.</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">
<b>Currency Risk:</b> Fluctuations in the exchange rates between different currencies may negatively affect an investment. The Fund may be subject to currency risk because it may invest in securities or other instruments that generate income denominated in foreign currencies. The Fund may elect not to hedge currency risk, or may hedge such risk imperfectly, which may cause the Fund to incur losses that would not have been incurred had the risk been hedged. </p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">
<b>Derivatives Risk:</b> Derivative instruments (such as those in which the Fund may invest, including futures transactions) are subject to changes in the value of the underlying assets or indices on which such instruments are based. There is no guarantee that the use of derivatives will be effective or that suitable transactions will be available. Even a small investment in derivatives may give rise to leverage risk and can have a significant impact on the Fund's exposure to securities markets values, interest rates or currency exchange rates. It is possible that the Fund's liquid assets may be insufficient to support its obligations under its derivatives positions. The use of derivatives for other than hedging purposes may be considered a speculative activity, and involves greater risks than are involved in hedging. The use of derivatives may cause the Fund to incur losses greater than those that would have occurred had derivatives not been used. The Fund's use of derivatives involves other risks, such as the credit risk relating to the other party to a derivative contract (which is greater for swaps and other OTC derivatives), the risk of difficulties in pricing and valuation, the risk that changes in the value of a derivative may not correlate as expected with changes in the value of relevant assets, rates or indices, liquidity risk, allocation risk and the risk of losing more than the initial margin required to initiate derivatives positions. There is also the risk that the Fund may be unable to terminate or sell a derivatives position at an advantageous time or price. The Fund's derivative counterparties may experience financial difficulties or otherwise be unwilling or unable to honor their obligations, possibly resulting in losses to the Fund. </p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">
<b>Emerging Markets Risk:</b> In addition to the risks of investing in foreign investments generally, emerging markets investments are subject to greater risks arising from political or economic instability, nationalization or confiscatory taxation, currency exchange restrictions, sanctions by the U.S. government and an issuer's unwillingness or inability to make principal or interest payments on its obligations. Emerging markets companies may be smaller and have shorter operating histories than companies in developed markets.</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">
<b>Foreign Securities Risk:</b> Investments in foreign securities may be subject to greater political, economic, environmental, credit/counterparty and information risks. The Fund's investments in foreign securities also are subject to foreign currency fluctuations and other foreign currency-related risks. Foreign securities may be subject to higher volatility than U.S. securities, varying degrees of regulation and limited liquidity.</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">
<b>Interest Rate Risk:</b> Interest rate risk is the risk that the value of the Fund's investments will fall if interest rates rise. The value of zero coupon bonds may be more sensitive to fluctuations in interest rates than other fixed-income securities. Generally, the value of fixed-income securities rises when prevailing interest rates fall and falls when interest rates rise. Interest rate risk generally is greater for funds that invest in fixed-income securities with relatively longer durations than for funds that invest in fixed-income securities with shorter durations. In addition, an economic downturn or period of rising interest rates could adversely affect the market for these securities and reduce the Fund's ability to sell them, negatively impacting the performance of the Fund.</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">
<b>Leverage Risk:</b> Use of derivative instruments may involve leverage. Leverage is the risk associated with securities or practices that multiply small index, market or asset-price movements into larger changes in value. The use of leverage increases the impact of gains and losses on the Fund's returns, and may lead to significant losses if investments are not successful.</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">
<b>Liquidity Risk:</b> Liquidity risk is the risk that the Fund may be unable to find a buyer for its investments when it seeks to sell them or to receive the price it expects. Decreases in the number of financial institutions willing to make markets in the Fund's investments or in their capacity or willingness to transact may increase the Fund's exposure to the risk. Events that may lead to increased redemptions, such as market disruptions or increases in interest rates, may also negatively impact the liquidity of the Fund's investments when it needs to dispose of them. If the Fund is forced to sell its investments at an unfavorable time and/or under adverse conditions in order to meet redemption requests, such sales could negatively affect the Fund. Securities acquired in a private placement, such as Rule 144A securities, are generally subject to significant liquidity risk because they are subject to strict restrictions on resale and there may be no liquid secondary market or ready purchaser for such securities. Non-exchange traded derivatives are generally subject to greater liquidity risk as well. Liquidity issues may also make it difficult to value the Fund's investments.</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">
<b>Management Risk:</b> A strategy used by the Fund's portfolio managers may fail to produce the intended result. </p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">
<b>Market/Issuer Risk:</b> The market value of the Fund's investments will move up and down, sometimes rapidly and unpredictably, based upon overall market and economic conditions, as well as a number of reasons that directly relate to the issuers of the Fund's investments, such as management performance, financial condition and demand for the issuers' goods and services. </p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">
<b>Mortgage-Related and Asset-Backed Securities Risk:</b> In addition to the risks associated with investments in fixed-income securities generally (for example, credit, liquidity and valuation risk), mortgage-related and asset-backed securities are subject to the risks of the mortgages and assets underlying the securities as well as prepayment risk, the risk that the securities may be prepaid and result in the reinvestment of the prepaid amounts in securities with lower yields than the prepaid obligations. Conversely, there is a risk that a rise in interest rates will extend the life of a mortgage-related or asset-backed security beyond the expected prepayment time, typically reducing the security's value, which is called extension risk. The Fund also may incur a loss when there is a prepayment of securities that were purchased at a premium. The Fund's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets.</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">
<b>REITs Risk:</b> Investments in the real estate industry, including REITs, are particularly sensitive to economic downturns and are sensitive to factors such as changes in real estate values, property taxes and tax laws, interest rates, cash flow of underlying real estate assets, occupancy rates, government regulations affecting zoning, land use and rents and the management skill and creditworthiness of the issuer. Companies in the real estate industry also may be subject to liabilities under environmental and hazardous waste laws. In addition, the value of a REIT is affected by changes in the value of the properties owned by the REIT or mortgage loans held by the REIT. REITs are also subject to default and prepayment risk. Many REITs are highly leveraged, increasing their risk. The Fund will indirectly bear its proportionate share of expenses, including management fees, paid by each REIT in which it invests in addition to the expenses of the Fund.</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;"><b>
Risk/Return Bar Chart and Table
</b></p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">The following bar chart and table provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year-to-year and by showing how the Fund's average annual returns for the one-year, five-year and ten-year periods compare to those of a broad measure of market performance. The Fund's past performance (before and after taxes) does not necessarily indicate how the Fund will perform in the future. Updated performance information is available online at ngam.natixis.com and/or by calling the Fund toll-free at 800-225-5478.</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">The chart does not reflect any sales charge that you may be required to pay when you buy or redeem the Fund's shares. A sales charge will reduce your return.</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">
<b>Total Returns for Class T Shares </b>
</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">
Highest Quarterly Return: <br />
Second Quarter 2009, 7.47%
</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">
Lowest Quarterly Return: <br />
Third Quarter 2008, -3.02%
</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;"><b>Average Annual Total Returns</b> </p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;"><b>
(for the periods ended December 31, 2016) </b> </p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">The Fund did not have Class T shares outstanding during the periods shown above. The returns of Class T shares would have been substantially similar to the returns of the Fund's other share classes because they would have been invested in the same portfolio of securities and would only differ to the extent the other share classes did not have the same expenses. Performance of Class T shares shown above is that of Class A shares, which have the same expenses as Class T shares, restated in the table to reflect the different sales load applicable to Class T shares.</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">Effective August 31, 2016, the Fund's Retail Class shares were redesignated as Class A shares. Accordingly, the returns shown in the bar chart for Class A shares prior to August 31, 2016 are those of Retail Class shares and the returns shown in the table for Class T shares prior to August 31, 2016 are those of Retail Class shares restated to reflect the sales load of Class T shares. Prior to the inception of Retail Class shares (May 28, 2010), performance is that of Institutional Class shares, restated to reflect the higher net expenses of Class A shares in the bar chart and restated to reflect the higher net expenses and sales loads of Class T shares in the table. The Fund revised its investment strategies on May 28, 2010; performance may have been different had the current investment strategies been in place for all periods shown.</p>
<p style="font-size:10pt;padding-top:2;padding-bottom:0;padding-left:0;">After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their shares through tax-advantaged arrangements, such as 401(k) plans, qualified plans, education savings accounts, such as 529 plans, or individual retirement accounts. The after-tax returns are shown for only one class of the Fund. After-tax returns for the other classes of the Fund will vary. Index performance reflects no deduction for fees, expenses or taxes.</p>
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0.025
0
0
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0.0025
0.0022
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0.0065
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0.0534
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0.187
0.0761
0.0518
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0.0351
0.0051
0.0258
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-0.011
0.0002
0.0208
0.0173
0.0061
0.0086
0.0185
0.0413
0.0275
0.0267
0.0384
You may qualify for a sales charge discount if you invest at least $250,000 in the Fund.
January 31, 2019
1.51
250000
You may lose money by investing in the Fund.
The Fund's past performance (before and after taxes) does not necessarily indicate how the Fund will perform in the future.
The following bar chart and table provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year-to-year and by showing how the Fund's average annual returns for the one-year, five-year and ten-year periods compare to those of a broad measure of market performance.
The chart does not reflect any sales charge that you may be required to pay when you buy or redeem the Fund's shares. A sales charge will reduce your return.
Highest Quarterly Return: Second Quarter 2009, 7.47%
0.0747
2009-06-30
Lowest Quarterly Return: Third Quarter 2008, -3.02%
-0.0302
2008-09-30
ngam.natixis.com
800-225-5478
After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.
After-tax returns shown are not relevant to investors who hold their shares through tax-advantaged arrangements, such as 401(k) plans, qualified plans, education savings accounts, such as 529 plans, or individual retirement accounts.
After-tax returns for the other classes of the Fund will vary.
Index performance reflects no deduction for fees, expenses or taxes.
Other expenses are estimated for the current fiscal year.
Other expenses are estimated for the current fiscal year.
Loomis, Sayles & Company, L.P. ("Loomis Sayles" or the "Adviser") has given a binding contractual undertaking to the Fund to limit the amount of the Fund's total annual fund operating expenses to 0.65% of the Fund's average daily net assets for Class T shares, exclusive of brokerage expenses, interest expense, taxes, acquired fund fees and expenses, organizational and extraordinary expenses, such as litigation and indemnification expenses. This undertaking is in effect through January 31, 2019 and may be terminated before then only with the consent of the Fund's Board of Trustees. The Adviser will be permitted to recover, on a class by class basis, management fees waived and/or expenses reimbursed to the extent that expenses in later periods fall below the applicable expense limitation for Class T shares. The Fund will not be obligated to repay any such waived/reimbursed fees and expenses more than one year after the end of the fiscal year in which the fees or expenses were waived/reimbursed.