In the Chelsea Republican caucuses held on November 24, 1896, Pratt received the Republican nomination Mayor of Chelsea, beating Seth J. Littlefield by 214 Votes.

[3] In December 1896 Pratt was elected Mayor of Chelsea by a Plurality of 2,305 votes over John T Hadaway President of the Chelsea Board of Aldermen.

[2] In November 1897 Pratt announced that he would not be a candidate for reelection.

[4] After he was mayor Pratt served as the President of the Chelsea Board of Trade.

Pratt died May 2, 1918[1] at Whidden Hospital, Everett, Massachusetts,[1] as a result of illness with which he was stricken on April 16, 1918.