Date of Formation: April 19, 1856

Services Provided: Assessor-county clerk-recorder, coroner, corrections, elections, emergency services, environmental management, health services, parks and recreation, planning, probation, public works, sheriff, social services, plus various municipal services in unincorporated areas

Area: 455 square miles

Population: 774,485 (CA Department of Finance 2019)


General Inquiries: (650) 363-4123
Hours: 8:00 am – 5:00 pm, Monday through Friday

MICHAEL CALLAGY, County Executive Officer/Clerk of the Board
(650) 363-4123

Board of Supervisors

The San Mateo County Board of Supervisors is composed of five members elected to four-year terms by the public in their respective districts (see FIND YOUR DISTRICT on the Board of Supervisors website).

District Supervisor Term Ending
1 Dave Pine 2024
2 Noelia Corzo 2026
3 Ray Mueller 2026
4 Warren Slocum 2024
5 David Canepa


See Public Meetings on the county website for the current meeting schedule.

All meetings are held at the Board of Supervisors’ Chambers, 400 County Center, Redwood City, CA 94063

Meeting time is 9:00 am unless otherwise noted in the agenda. Future agendas are posted one week prior to the meeting date.

County Map