County outline
Where San Francisco County is located
Area breakdown
Land accounts for 20.1% of San Francisco County’s measured area and water for 79.9%. Its combined area converts to 600.6 square kilometers or approximately 148,415 acres.
Green: land · blue: water
| Measurement | Square miles | Square kilometers | Acres |
|---|---|---|---|
| Land | 46.685 | 120.914 | 29,878.4 |
| Water | 185.214 | 479.702 | 118,537 |
| Total | 231.899 | 600.616 | 148,415.4 |
How San Francisco County compares
By original Census land area, San Francisco County ranks #58 of 58 in California and #3133 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.
Its land area is 0.03 times the California county-equivalent median of 1,535.7 square miles. It accounts for 0% of the combined county land area in the state.
See the complete California ranking · What counts as a county equivalent?
What stands out about San Francisco County?
San Francisco County has more land than 89 of the other 3,221 county equivalents in the dataset.
A median is the middle county-equivalent measurement, not the average of the largest and smallest. All three bars use the same linear scale. Very small areas may appear as a thin sliver; the labels retain their values.
Does including water change its rank?
Using land plus water places San Francisco County at #2,979 nationally by total area, 154 places closer to the top than its land rank. The water assigned to this geography moves it ahead of some county equivalents with more land.
Its water share is 79.9%, compared with a national county-equivalent median of 1.2% — 78.7 percentage points higher. This describes the statistical geography’s land/water mix, not flood exposure or developable land.
Closest positions in the national land ranking
These entries sit immediately beside San Francisco County in the national ranking. They can be in different states and are not necessarily geographic neighbors.
| Land rank | County equivalent | Land mi² | Comparison |
|---|---|---|---|
| #3132 | San Juan Municipio, Puerto Rico | 47.9 | Compare |
| #3133 | San Francisco County, California | 46.7 | This county |
| #3134 | Patillas Municipio, Puerto Rico | 46.6 | Compare |
Calculated from the same Census release as the area table. Total-area order uses original ALAND + AWATER; water shares and chart labels use published square miles. Calculation details.
Representative coordinates
The Census internal point is 37.727239, -123.032229. It represents a location inside the geography; it is not necessarily the centroid or the address of a courthouse.
Source and precision
U.S. Census Bureau, 2026 Gazetteer Files, Counties. Original ALAND: 120,913,761 m²; AWATER: 479,701,779 m². Rankings use ALAND; exact ties use ascending GEOID. Tables preserve Census-published square miles to three decimals, with conversions based on those values.
Common questions
How many acres of land are in San Francisco County?
The land measurement converts to approximately 29,878 acres. Including water, total area is approximately 148,415 acres. One square mile equals 640 acres.
Why might another source show a different area?
Check whether it reports land or total area, its Census vintage, and its rounding. Our guide explains how to reconcile county area figures.
Can this establish a property boundary?
No. Statistical measurements and generalized maps do not establish property lines. Consult the relevant local surveying or land-records authority.