South San Francisco, California

South San Francisco population, 2020 to 2024

South San Francisco lost 1,243 residents from July 2020 to July 2024, a change of -1.9%. In the latest year it moved by +922. Among 429 California places of 5,000 or more, that growth ranks 268th; the median place changed by -1.1%. The median place of 5,000+ in California has 37,056 people, so South San Francisco is 1.7 times that size.

South San Francisco covers 9.20 square miles of land and 20.97 of water, for 7,028 people per square mile of land. The median California place of 5,000+ has 3,725, so South San Francisco is denser than the typical town.

What county South San Francisco is in

All of South San Francisco's residents live in San Mateo County, which had 742,893 residents in 2024. South San Francisco holds 8.7% of the county's population. The shaded shape is on the map above; dots mark the eight nearest places.

ZIP codes in South San Francisco

1 ZIP Code Tabulation Area (ZCTA) overlaps South San Francisco by at least 10% of the ZCTA's or the city's land: 94080. ZCTAs are Census approximations of USPS ZIP code delivery areas. The list comes from the 2020 ZCTA to place relationship file, so a city that annexed land after 2020 may reach into ZIP codes not listed here.

Where South San Francisco is

The Census internal point of South San Francisco is at 37.655100, -122.376200. Sacramento, the capital, is 79.7 miles NE in a straight line. The nearest larger place is Daly City, CA (101,418 people), 5.8 miles away.

Daylight in South San Francisco

At 37.66° N, South San Francisco gets about 14 h 46 min of daylight around the June solstice and 9 h 34 min around the December solstice, a swing of 5 h 13 min. Figures are sunrise to sunset from the SunCalc model for June 21 and December 21, 2026.

Places near South San Francisco

The eight nearest incorporated places of 1,000+ in California, measured between internal points. The closest is Brisbane, 1.5 miles away, with 4,667 people.