Montgomery Street Income Securities, Inc. Announces New Investment Adviser and Administrator.

SAN FRANCISCO -- The Board of Directors of Montgomery Street Income Securities, Inc. (NYSE: MTS) (the "Fund") announced today that it has concluded its search for a new investment adviser and administrator.

Effective June 9, 2006, Hartford Investment Management Company ("HIMCO") will become the investment adviser, and Jackson Fund Services ("JFS"), a division of Jackson National Asset Management, LLC, will become the administrator, of the Fund. On the same date, Mark D. Nerud will become President and Chief Executive Officer, and Jeffrey C. Nellessen will become Treasurer and Chief Financial Officer, of the Fund. Messrs. Nerud and Nellessen are affiliated with JFS.

HIMCO, based in Hartford, Connecticut, manages approximately $117 billion in total assets, roughly $111 billion of which are invested in fixed income assets. JFS, based in Chicago, provides administrative services to 93 funds with approximately $46 billion in assets.

HIMCO and JFS succeed Deutsche Investment Management Americas Inc. ("DIMA") as the Fund's adviser and administrator. The Board of Directors had commenced a search for a new adviser and administrator after DIMA's parent, Deutsche Bank, N.A., agreed to sell parts of its asset management business to Aberdeen Asset Management PLC ("Aberdeen PLC") and members of the Fund's portfolio management team moved to an Aberdeen PLC affiliate.

The Board of Directors has approved an interim contract with HIMCO that will begin on June 9, 2006 and continue until the earlier of November 6, 2006 or the date a definitive contract is approved by stockholders. The Fund intends to present a definitive contract with HIMCO for approval by stockholders at the Fund's Annual Meeting of Stockholders currently scheduled for July 13, 2006. Proxy materials will be sent to stockholders in advance of the Annual Meeting.

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.

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, circular or representation intended for use in the purchase or sale of Fund shares, or a proxy solicitation. (4/06 41800)

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