Santa Clara County area

Population and density of Santa Clara County

The Census Bureau estimates that 1,914,391 people lived in Santa Clara County on July 1, 2025. That ranks #18 of 3,222 county equivalents nationally and #6 of 58 in California. Since the April 1, 2020 estimates base of 1,936,274, the population has declined by 21,883 (−1.1%), compared with −0.5% for California as a whole.

With 1,291.1 square miles of land, that is 1,483 people per square mile (573 per km²), placing Santa Clara County #119 nationally for density and #8 in California. The median county equivalent has 47 people per square mile; the California median is 112. Put another way, there are about 0.432 acres of land per resident.

U.S. Census Bureau, Vintage 2025 population estimates. Estimates are revised each year and are not decennial census counts. Density divides the whole population by the whole county’s land area, so it describes an average, not how settlement is distributed within the county. Population sources and methods.

Cities and towns in Santa Clara County

15 incorporated places lie at least partly in Santa Clara County. Together they are home to 1,824,636 people (95.3%); the other 89,755 (4.7%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is San Jose city, with 989,814 residents in the county. Among places with at least 1,000 residents in 2020, Santa Clara city grew fastest since then (+4.3%).

Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each place inside Santa Clara County. Land: 2026 Census Gazetteer, for the whole place even where it extends into other counties. How communities are listed.

Metropolitan area

Santa Clara County is a central county of the San Jose-Sunnyvale-Santa Clara, CA Metropolitan Statistical Area. Its 2 county equivalents have 1,984,473 residents on 2,679.7 square miles of land; Santa Clara County accounts for 48.2% of the land and 96.5% of the residents. By combined land it ranks #120 of 393 metropolitan areas, and #37 by population. It belongs to the San Jose-San Francisco-Oakland, CA Combined Statistical Area.

ZIP codes

63 ZIP Code Tabulation Areas have land in Santa Clara County; 58 of them have most of their land inside the county, and the others mainly cover neighboring areas.

940229402494028940409404194043940859408694087940899430194303943049430594306945509500295008950139501495020950239503095032950339503595037950469505095051950539505495070950769511095111951129511395116951179511895119951209512195122951239512495125951269512795128951299513095131951329513395134951359513695138951399514095148

ZIP Code Tabulation Areas are the Census Bureau’s approximations of USPS ZIP Code service areas, from the 2020 Census relationship files. Lighter codes have less than half of their land in this county. Post-office-box and single-address ZIP Codes have no tabulation area.

Counties bordering Santa Clara County

Santa Clara County shares a land border with 6 county equivalents. It has more land than 3 of them. The largest neighbor is Merced County (1,938 mi²) and the smallest is Santa Cruz County (445.1 mi²). Together with its neighbors, Santa Clara County forms a block of 7,745.1 mi² of land, of which it holds 16.7%.

How big is Santa Clara County compared with U.S. states?

Santa Clara County has more land than 1 of the 50 states. It is about 1.2 times the land area of Rhode Island (1,033.9 mi²), while Delaware, the next larger state, has 1.5 times as much land (1,948.6 mi²). California’s county land could hold about 121 areas the size of Santa Clara County.

Another way to picture it: the same land area would fill a square about 35.9 miles (57.8 km) on each side. Real county shapes are rarely square, so this is a scale reference rather than a width or driving distance.

State figures are the sums of each state’s county-equivalent land measurements in the same Census release, so states and counties are compared on the same basis. Published state totals can differ slightly because of rounding. Compare all states · Counties bigger than entire states.

What stands out about Santa Clara County?

Santa Clara County has more land than 2,758 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 Santa Clara County at #528 nationally by total area, 64 places farther from the top than its land rank. Other county equivalents gain more area when their water measurements are included.

Its water share is 1%, compared with a national county-equivalent median of 1.2% — 0.2 percentage points lower. 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 Santa Clara County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

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.