The 2017 Pittsburgh mayoral election took place on November 7, 2017. The primary election was held on May 16, 2017. Incumbent Democratic Mayor Bill Peduto successfully ran for re-election to a second term. Three Democrats, including Peduto, and no Republicans filed petitions to appear on the respective primary ballots before the deadline on March 7, 2017. Peduto won the Democratic primary and was officially unopposed in the general election.
The 2013 election, in which then-incumbent Mayor Luke Ravenstahl was originally a candidate for re-election before withdrawing, saw an open election for Mayor of Pittsburgh. Then-city council member Bill Peduto, who had run for Mayor of Pittsburgh in the 2005 election and the 2007 special election following the death of Bob O'Connor, won a four-way Democratic primary. He went on to win the general election comfortably, defeating his Republican opponent, Joshua Wander, by 73 points. He assumed office in January 2014.
The Democratic primary election was held on May 16, 2017. Incumbent Mayor Bill Peduto formally announced his re-election campaign on December 14, 2016. Peduto's first challenger, activist John Welch, declared his candidacy on January 21. In mid-February 2017, two individuals had filed to vie for the primary election endorsement of the Allegheny County Democratic Committee: Peduto and city council member Darlene Harris, the latter of whom had not officially announced a campaign. John Welch did not file for the committee endorsement, but remained a candidate in the primary.
The committee announced its endorsement of Bill Peduto on March 5. Harris, although losing the party endorsement, gained 40% of the committee votes and filed petitions just before the March 7 deadline to appear on the ballot in the primary, despite not having formed an official campaign. Because of this, Harris did not file a campaign finance report and challenged the legality of the city ordinance requiring them.
No Republican received the requisite 250 write-in votes in the Republican primary to become that party's nominee, but Peduto received 228 write-ins, Darlene Harris received 229, and John Welch received 65, with 21 votes that had not been verified. Two independent candidates—James Rack and Khalid Raheem—filed to appear on the ballot before the early August 2017 deadline, but were removed from the ballot in late August after their nominating petitions were successfully challenged by the Allegheny County Democratic Party. Rack had failed to provide a financial interest statement to the city clerk and Raheem's petition contained too few city resident signatures to qualify. Ultimately, Peduto was re-elected, having been the only candidate listed on the general election ballot.