Conference Call on Pioneer High Income Trust (PHT) to Be Held on Wednesday, August 15, 2007 at 4:00 P.M. EDT

Pioneer Investment Management, Inc. (“Pioneer Investments”) has announced that it will hold a conference call regarding Pioneer High Income Trust (NYSE: PHT).

The conference call will be held on Wednesday, August 15th at 4:00 p.m. EDT, and can be accessed by calling 1-866-360-7030 (Conference ID # 11908721). The call will be available on replay (for the week following the call) at 1-800-642-1687, and a transcript will be posted to pioneerinvestments.com.

Pioneer Investment Management, Inc., the investment advisor for these funds, is part of Pioneer Investment Management USA Inc., the U.S. subsidiary of Pioneer Global Asset Management S.p.A. Pioneer Global and its affiliates manage over $321 billion in assets (as of June 30, 2007), including approximately $83 billion managed in the U.S.

Closed-end funds, unlike open-end funds, are not continuously offered. There is a one-time public offering and once issued, shares of closed-end funds are sold in the open market through a stock exchange and frequently trade at prices lower than their net asset value. Net asset value (NAV) is total assets less total liabilities divided by the number of common shares outstanding.

Please consider the fund's investment objectives, risks, charges and expenses carefully before investing. The prospectus contains this and other information about the fund and should be read carefully before you invest or send money. To obtain a prospectus and for other information on Pioneer funds, contact your advisor or visit our web site: pioneerinvestments.com.

Pioneer Funds Distributor, Inc., Member SIPC

©2007 Pioneer Investment Management, Inc. 60 State Street Boston, MA 02109

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