Oppenheimer Capital Income Fund

Supplement dated September 3, 2013 to the

Prospectus and Statement of Additional Information, each dated December 28, 2012

This supplement amends the Prospectus and Statement of Additional Information (“SAI”) of the above referenced fund (the “Fund”), each dated December 28, 2012, and is in addition to any other supplement(s).

Effective November 1, 2013:

1. The fourth paragraph in the section titled “Principal Investment Strategies” on page 4 of the Prospectus is deleted in its entirety and replaced by the following:

The Fund's debt securities may be rated by a nationally recognized statistical rating organization or may be unrated. The Fund can invest up to 40% of its total assets in below-investment-grade securities, also referred to as "junk bonds." "Investment grade" securities are rated in one of the top four rating categories.

2. The section titled “Special Risks of Lower-Grade Securities” on page 5 of the Prospectus is deleted in its entirety and replaced by the following:

Special Risks of Below-Investment-Grade Securities. Below-investment-grade debt securities (also referred to as “junk” bonds) may be subject to greater price fluctuations than investment-grade securities, increased credit risk and greater risk that the issuer might not be able to pay interest and principal when due. The market for below-investment-grade securities may be less liquid and therefore these securities may be harder to value or sell, especially during times of market volatility or decline.

Because the Fund can invest up to 40% of its assets in below-investment-grade securities, the Fund’s credit risks are greater than those of funds that buy only investment-grade securities. This restriction is applied at the time of purchase and the Fund may continue to hold a security whose credit rating has been downgraded or, in the case of an unrated security, after the Fund’s Sub-Adviser has changed its assessment of the security’s credit quality. As a result, credit rating downgrades or other market fluctuations may cause the Fund’s holdings of below-investment-grade securities to exceed, at times significantly, this restriction for an extended period of time. Credit rating downgrades of a single issuer or related similar issuers whose securities the Fund holds in significant amounts could substantially and unexpectedly increase the Fund’s exposure to below-investment-grade securities and the risks associated with them, especially liquidity and default risk. If the Fund has more than 40% of its total assets invested in below-investment-grade securities, the Sub-Adviser will not purchase additional below-investment-grade securities until the level of holdings in those securities no longer exceeds the restriction.

3. The following is added to the section titled “About the Fund’s Investments” beginning on page 7 of the Prospectus:

Risks of Below-Investment-Grade Securities. Below-investment-grade securities (also referred to as “junk bonds”) generally have higher yields than securities rated in the higher rating categories but also have higher risk profiles. Below-investment-grade securities are considered to be speculative and entail greater risk with respect to the ability of the issuer to timely repay principal and pay interest or dividends in accordance with the terms of the obligation and may have more credit risk than investment-grade rated securities. These additional risks mean that the Fund may not receive the anticipated level of income from these securities, and the Fund’s net asset value may be affected by declines in the value of lower-grade securities. The major risks of below-investment-grade securities include:

· Prices of below-investment-grade securities are subject to extreme price fluctuations, even under normal market conditions. Adverse changes in an issuer’s industry and general economic conditions may have a greater impact on the prices of below-investment-grade securities than on the prices of investment-grade fixed income securities.

· Below-investment-grade securities may be issued by less creditworthy issuers and may be more likely to default than investment-grade securities. Issuers of below-investment-grade securities may have more outstanding debt relative to their assets than issuers of investment-grade securities. Issuers of below-investment-grade securities may be unable to meet their interest or principal payment obligations because of an economic downturn, specific issuer developments, or the unavailability of additional financing.

· In the event of an issuer’s bankruptcy, claims of other creditors may have priority over the claims of below-investment-grade securities holders.

· Below-investment-grade securities may be less liquid than investment-grade fixed income securities, even under normal market conditions. There are fewer dealers in the below-investment-grade securities market and there may be significant differences in the prices quoted by the dealers. Because they are less liquid, judgment may play a greater role in valuing certain of the Fund’s securities than is the case with securities trading in a more liquid market.

· Below-investment-grade securities typically contain redemption provisions that permit the issuer of the securities containing such provisions to redeem the securities at its discretion. If the issuer redeems below-investment-grade securities, the Fund may have to invest the proceeds in securities with lower yields and may lose income.

· Below-investment-grade securities markets may be more susceptible to real or perceived adverse credit, economic, or market conditions than investment-grade securities.

The Fund can invest up to 40% of its total assets in below-investment-grade securities. This restriction is applied at the time of purchase and the Fund may continue to hold a security whose credit rating has been downgraded or, in case of an unrated security, after the Fund's Sub-Adviser has changed its assessment of the security's credit quality. As a result, credit rating downgrades or other market fluctuations may cause the Fund's holdings of below-investment-grade securities to exceed, at times significantly, this restriction for an extended period of time. Credit rating downgrades of a single issuer or related similar issuers whose securities the Fund holds in significant amounts could substantially and unexpectedly increase the Fund’s exposure to below-investment-grade securities and the risks associated with them, especially liquidity and default risk. If the Fund has more than 40% of its total assets invested in below-investment-grade securities, the Sub-Adviser will not purchase additional below-investment-grade securities until the level of holdings in those securities no longer exceeds the restriction.

4. The second paragraph in the section titled “Illiquid and Restricted Securities” on page 11 of the Prospectus is deleted in its entirety and replaced by the following:

The Fund will not invest more than 15% of its net assets in illiquid securities. The Sub-Adviser monitors the Fund's holdings of illiquid securities on an ongoing basis to determine whether to sell any of those securities to maintain adequate liquidity.

5. The section titled “Special Risks of Lower-Grade Securities” beginning on page 4 of the SAI is deleted in its entirety and replaced by the following:

Special Risks of Below-Investment-Grade Securities. While below-investment-grade securities generally may have a higher yield than securities rated in the higher rating categories, they are subject to increased risks. Below-investment-grade securities are considered to be speculative with respect to the ability of the issuer to timely repay principal and pay interest or dividends in accordance with the terms of the obligation and may have more credit risk than investment-grade securities. The major risks of below-investment-grade securities include:

· Prices of below-investment-grade securities are subject to extreme price fluctuations, even under normal market conditions. Negative economic developments may have a greater impact on the prices of below-investment-grade securities than on those of other investment-grade fixed income securities. In addition, the market values of below-investment-grade securities tend to reflect individual issuer developments to a greater extent than do the market values of investment-grade securities, which react primarily to fluctuations in the general level of interest rates.

· Below-investment-grade securities may be issued by less creditworthy issuers and may be more likely to default than investment-grade securities. The issuers of below-investment-grade securities may have more outstanding debt relative to their assets than issuers of investment-grade securities. Below-investment-grade securities are vulnerable to adverse changes in the issuer’s industry and to general economic conditions. If the issuers experiences financial stress, it may not be able to pay interest and principal payments in a timely manner. The issuer’s ability to pay its debt obligations also may be lessened by specific issuer developments or the unavailability of additional financing. In the event of a default of an issuer of a below-investment-grade security, the Fund may incur expenses to the extent necessary to seek recovery or to negotiate new terms.

· Below-investment-grade securities are frequently ranked junior to claims by other creditors. If the issuer cannot meet its obligations, the senior obligations are generally paid off before the junior obligations, which could limit the Fund’s ability to fully recover principal or to receive interest payments when senior securities are in default. As a result, investors in below-investment-grade securities have a lower degree of protection with respect to principal and interest payments than do investors in investment-grade securities.

· There may be less of a market for below-investment securities and as a result they may be harder to sell at an acceptable price. Not all dealers maintain markets in all below-investment-grade securities. As a result, there is no established retail secondary market for many of these securities. The Fund anticipates that such securities could be sold only to a limited number of dealers or institutional investors. To the extent a secondary trading market does exist, it is generally not as liquid as the secondary market for investment-grade securities. The lack of a liquid secondary market may have an adverse impact on the market price of the security. The lack of a liquid secondary market for certain securities may also make it more difficult for the Fund to obtain accurate market quotations for purposes of valuing its securities. Market quotations are generally available on many below-investment-grade securities only from a limited number of dealers and may not necessarily represent firm bids of such dealers or prices for actual sales. In addition, the trading volume for below-investment-grade securities is generally lower than that for investment-grade securities and the secondary markets could contract under adverse market or economic conditions independent of any specific adverse changes in the condition of a particular issuer. Under certain economic and/or market conditions, the Fund may have difficulty disposing of certain below-investment-grade securities due to the limited number of investors in that sector of the market. When the secondary market for below-investment-grade securities becomes more illiquid, or in the absence of readily available market quotations for such securities, the relative lack of reliable objective data makes it more difficult to value the Fund’s securities and judgment plays a more important role in determining such valuations.

· Below-investment-grade securities frequently have redemption features that permit an issuer to repurchase the security from the Fund before it matures. During times of falling interest rates, issuers of these securities are likely to redeem or prepay the securities and reissue securities with a lower interest rate. To the extent an issuer is able to refinance the securities, or otherwise redeem them, the Fund may have to replace the securities with lower yielding securities which could result in a lower return for the Fund.

· Below-investment-grade securities markets may also react strongly to adverse news about an issuer or the economy, or to the perception or expectation of adverse news, whether or not it is based on fundamental analysis. An increase in interest rates could severely disrupt the market for below-investment-grade securities. Additionally, below-investment-grade securities may be affected by legislative and regulatory developments. These developments could adversely affect a Fund’s net asset value and investment practices, the secondary market for below-investment-grade securities, the financial condition of issuers of these securities and the value and liquidity of outstanding below-investment-grade securities, especially in a thinly traded market.

These additional risks mean that the Fund may not receive the anticipated level of income from these securities, and the Fund's net asset value may be affected by declines in the value of lower-grade securities. Credit rating downgrades of a single issuer or related similar issuers whose securities the Fund holds in significant amounts could substantially and unexpectedly increase the Fund’s exposure to below-investment-grade securities and the risks associated with them, especially liquidity and default risk.

While securities rated "Baa" by Moody's, "BBB" by S&P, or the similar category by the Sub-Adviser if an unrated security, are investment-grade, they may be subject to special risks and have some speculative characteristics.

September 3, 2013 PS0300.042