Adams County Flag

Adams County

State:
Washington
County Seat:
Ritzville

Adams County's estimated 2026 population is 21,654 with a growth rate of 0.77% in the past year according to the most recent United States census data. Adams County is the 31st largest county in Washington. The 2010 population was 18,791 and has seen a growth of 15.24% since that time.

21,654
Total Population
11
Population Density (mi²)
31
Population Rank (State)
166 0.77%
Annual Population Growth

Adams County Population

Demographics

Economics and Income Statistics