Riverside County area

Population and density of Riverside County

The Census Bureau estimates that 2,544,916 people lived in Riverside County on July 1, 2025. That ranks #10 of 3,222 county equivalents nationally and #4 of 58 in California. Since the April 1, 2020 estimates base of 2,419,962, the population has grown by 124,954 (+5.2%), compared with −0.5% for California as a whole.

With 7,209 square miles of land, that is 353 people per square mile (136 per km²), placing Riverside County #451 nationally for density and #16 in California. The median county equivalent has 47 people per square mile; the California median is 112. Put another way, there are about 1.8 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 Riverside County

28 incorporated places lie at least partly in Riverside County. Together they are home to 2,112,376 people (83%); the other 432,540 (17%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Riverside city, with 323,057 residents in the county. By land, Palm Springs city is the largest at 94.5 mi². Among places with at least 1,000 residents in 2020, Menifee city grew fastest since then (+15.7%).

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

Metropolitan area

Riverside County is a central county of the Riverside-San Bernardino-Ontario, CA Metropolitan Statistical Area. Its 2 county equivalents have 4,769,007 residents on 27,277.5 square miles of land; Riverside County accounts for 26.4% of the land and 53.4% of the residents. By combined land it ranks #1 of 393 metropolitan areas, and #12 by population. It belongs to the Los Angeles-Long Beach, CA Combined Statistical Area.

ZIP codes

76 ZIP Code Tabulation Areas have land in Riverside County; 71 of them have most of their land inside the county, and the others mainly cover neighboring areas.

91752920289220192203922109221192220922239222592230922349223692239922409224192253922549225892260922629226492270922749227692277922829232092324923739239992501925039250492505925069250792508925099251892521925309253292536925399254392544925459254892549925519255392555925579256192562925639256792570925719258292583925849258592586925879259092591925929259592596928609287992880928819288292883

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 Riverside County

Riverside County shares a land border with 5 county equivalents, including 1 in Arizona. It has more land than 4 of them. The largest neighbor is San Bernardino County (20,068.4 mi²) and the smallest is Orange County (793.2 mi²). Together with its neighbors, Riverside County forms a block of 40,953.6 mi² of land, of which it holds 17.6%.

How big is Riverside County compared with U.S. states?

Riverside County has more land than 4 of the 50 states. It is about 1.1 times the land area of Hawaii (6,422.6 mi²), while New Jersey, the next larger state, has 1 times as much land (7,355 mi²). California’s county land could hold about 22 areas the size of Riverside County.

Another way to picture it: the same land area would fill a square about 84.9 miles (136.6 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 Riverside County?

Riverside County has more land than 3,180 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 Riverside County at #47 nationally by total area, 5 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 1.3%, compared with a national county-equivalent median of 1.2% — 0.1 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 Riverside 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.