The 1963 Philadelphia's municipal election, held on November 5, involved contests for mayor, all seventeen city council seats, and several other executive and judicial offices. The Democrats lost vote share citywide and the Republicans gained one seat in City Council, but the Democratic acting mayor, James Tate, was elected to a full term and his party maintained their hold on the city government. The election was the first decline in the Democrats' share of the vote since they took control of the city government in the 1951 elections, and showed the growing tension between the reformers and ward bosses within their party.