Press Release FOR IMMEDIATE RELEASE For stockholder inquiries: Computershare Shareowner Services - (877) 437-3938 For media inquiries: Melissa Hernandez - (303) 224-7572 or (800) 565-9044 x 57572 MONTGOMERY STREET INCOME SECURITIES, INC. ANNOUNCES DISTRIBUTION SAN FRANCISCO - (December 13, 2013) - Montgomery Street Income Securities, Inc. (NYSE: MTS) (the "Fund") declared a dividend of $0.15 per share. The dividend is payable on December 31, 2013 to stockholders of record at the close of business on December 23, 2013.

The dividend reflects estimated tax adjustments which reduced distributable income by approximately $0.05 per share and an estimated return of capital of approximately $0.04 per share. The Board of Directors of the Fund determined to return this capital to stockholders in order to bring the dividend paid for the fourth quarter more closely in line with the dividend paid for the prior quarter.
For tax purposes, it is anticipated that approximately $0.64 of the distributions paid in 2013 will be distributions from ordinary income and $0.04 of the distributions paid in 2013 will be a return of capital. The actual sources of distributions will be reported to stockholders in January
2014 on Form 1099-DIV.

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The Fund is a closed-end diversified management investment company whose primary investment objective is to seek as high a level of current income as is consistent with prudent investment risks, from a diversified portfolio primarily of debt securities. The Fund's shares are traded on the New York Stock Exchange under the symbol MTS.
A return of capital distribution does not necessarily reflect the Fund's investment performance and should not be confused with "yield" or "income." Returns of capital are not taxable income to stockholders, but reduce the tax basis of stockholders in their Fund shares. The sources of the distributions reported in this press release are only estimates and are not being provided for tax reporting purposes.
Closed-end funds, unlike open-end funds, are not continuously offered. There is generally a one-time public offering and, once issued, shares of closed-end funds are sold in the open market through a stock exchange. Shares of closed-end funds frequently trade at a discount to net asset value.
The price of the Fund's shares is determined by a number of factors, several of which are beyond the control of the Fund. Therefore, the Fund cannot predict whether its shares will trade at, below or above net asset value.
Investments in funds involve risk. Yields and market values will fluctuate. Investing in foreign markets presents certain unique risks not associated with domestic investments, such as currency fluctuations, political and economic changes and market risks. Additionally, the Fund invests in lower-quality and non-rated securities, which present greater risks of loss of principal and interest than higher-quality securities. All of these factors may result in greater share price volatility.
This announcement is not an offer to purchase or the solicitation of an offer to sell shares of the Fund, a prospectus, a circular or representation intended for use in the purchase or sale of Fund shares, or a proxy solicitation

NOT FDIC/NCUA INSURED MAY LOSE VALUE NO BANK GUARANTEE NOT A DEPOSIT NOT INSURED BY ANY FEDERAL GOVERNMENT AGENCY

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