Chiu is set to make the announcement at a rally on the steps outside City Hall and then head to the elections office to officially file his declaration of intent to run, campaign manager Nicole Derse said.
Chiu is the latest entrant in an already crowded mayoral contest that will be decided in November.
State Sen. Leland Yee, City Attorney Dennis Herrera and former supervisors Bevan Dufty, Michaela Alioto-Pier and Tony Hall are among the other candidates in the running.
Chiu already served as acting mayor for one day in January. In accordance with the city charter, Chiu, who is president of the Board of Supervisors, held the position after Gavin Newsom was sworn in as the state’s lieutenant governor and before Ed Lee was sworn in as interim mayor.
Lee, formerly the city administrator, is expected to serve out the year as mayor and then return to his old job.
Chiu’s announcement is set to take place at 11 a.m. on the Polk Street side of City Hall.
Dan McMenamin, Bay City News