Asotin County area

Population and density of Asotin County

The Census Bureau estimates that 22,545 people lived in Asotin County on July 1, 2025. That ranks #1,755 of 3,222 county equivalents nationally and #30 of 39 in Washington. Since the April 1, 2020 estimates base of 22,292, the population has grown by 253 (+1.1%), compared with +3.8% for Washington as a whole.

With 636.1 square miles of land, that is 35 people per square mile (14 per km²), placing Asotin County #1,863 nationally for density and #22 in Washington. The median county equivalent has 47 people per square mile; the Washington median is 39. Put another way, there are about 18 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 Asotin County

2 incorporated places lie at least partly in Asotin County. Together they are home to 8,376 people (37.2%); the other 14,169 (62.8%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Clarkston city, with 7,189 residents in the county. The county seat, Asotin city, has 1,187 residents. Among places with at least 1,000 residents in 2020, Asotin city grew fastest since then (+0.8%).

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

Metropolitan area

Asotin County is a central county of the Lewiston, ID-WA Metropolitan Statistical Area. Its 2 county equivalents have 65,450 residents on 1,484.4 square miles of land; Asotin County accounts for 42.9% of the land and 34.4% of the residents. By combined land it ranks #220 of 393 metropolitan areas, and #388 by population.

ZIP codes

3 ZIP Code Tabulation Areas have land in Asotin County, and each lies mostly inside the county.

994019940299403

ZIP Code Tabulation Areas are the Census Bureau’s approximations of USPS ZIP Code service areas, from the 2020 Census relationship files. Post-office-box and single-address ZIP Codes have no tabulation area.

Counties bordering Asotin County

Asotin County shares a land border with 4 county equivalents, including 2 in Idaho and Oregon. Each of them has more land than Asotin County. The largest neighbor is Wallowa County (3,145.9 mi²) and the smallest is Garfield County (710.8 mi²). Together with its neighbors, Asotin County forms a block of 7,500.4 mi² of land, of which it holds 8.5%.

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

Asotin County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 1.6 times as much. Washington’s county land could hold about 104 areas the size of Asotin County.

Another way to picture it: the same land area would fill a square about 25.2 miles (40.6 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 Asotin County?

Asotin County has more land than 1,723 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 Asotin County at #1,611 nationally by total area, 112 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 0.7%, compared with a national county-equivalent median of 1.2% — 0.5 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 Asotin 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.