King County Flag

King County

State:
Washington
County Seat:
Seattle

King County's estimated 2026 population is 2,371,919 with a growth rate of 1.15% in the past year according to the most recent United States census data. King County is the largest county in Washington. The 2010 population was 1,938,431 and has seen a growth of 22.36% since that time.

2,371,919
Total Population
1,121
Population Density (mi²)
1
Population Rank (State)
27K 1.15%
Annual Population Growth

King County Population

Demographics

Economics and Income Statistics