Walla Walla County area

Population and density of Walla Walla County

The Census Bureau estimates that 62,361 people lived in Walla Walla County on July 1, 2025. That ranks #884 of 3,222 county equivalents nationally and #21 of 39 in Washington. Since the April 1, 2020 estimates base of 62,583, the population has declined by 222 (−0.4%), compared with +3.8% for Washington as a whole.

With 1,270 square miles of land, that is 49 people per square mile (19 per km²), placing Walla Walla County #1,569 nationally for density and #17 in Washington. The median county equivalent has 47 people per square mile; the Washington median is 39. Put another way, there are about 13 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 Walla Walla County

4 incorporated places lie at least partly in Walla Walla County. Together they are home to 45,534 people (73%); the other 16,827 (27%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Walla Walla city, with 34,058 residents in the county. Among places with at least 1,000 residents in 2020, Waitsburg city grew fastest since then (+2.1%).

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

Metropolitan area

Walla Walla County is a central county of the Walla Walla, WA Metropolitan Statistical Area. Walla Walla County is the area’s only county equivalent, so the metro area has the same 1,270 square miles of land. By combined land it ranks #246 of 393 metropolitan areas, and #390 by population. It belongs to the Kennewick-Richland-Walla Walla, WA Combined Statistical Area.

ZIP codes

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

9932399324993299934899360993619936299363

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 Walla Walla County

Walla Walla County shares a land border with 4 county equivalents, including 1 in Oregon. It has more land than 2 of them. The largest neighbor is Umatilla County (3,215.5 mi²) and the smallest is Columbia County (868.6 mi²). Together with its neighbors, Walla Walla County forms a block of 8,295.8 mi² of land, of which it holds 15.3%.

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

Walla Walla 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). Washington’s county land could hold about 52 areas the size of Walla Walla County.

Another way to picture it: the same land area would fill a square about 35.6 miles (57.4 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 Walla Walla County?

Walla Walla County has more land than 2,747 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 Walla Walla County at #533 nationally by total area, 58 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 2.2%, compared with a national county-equivalent median of 1.2% — 1.1 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 Walla Walla 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.