William Frank Mahoney (February 22, 1856 – December 27, 1904) was a U.S. representative from Illinois.

He was an alderman in the Chicago City Council from 1884 to 1887 and again from 1890 to 1896.

Mahoney was elected as a Democrat to the 57th and 58th Congresses and sat from March 4, 1901, until his death in Chicago on December 27, 1904.

[1] He was interred in Calvary Cemetery in Evanston, Illinois.

This article incorporates public domain material from the Biographical Directory of the United States Congress