King County Flag

King County

State:
Washington
County Seat:
Seattle

King County's estimated 2026 population is 2,427,007 with a growth rate of 1.82% 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 25.2% since that time.

2,427,007
Total Population
1,147
Population Density (mi²)
1
Population Rank (State)
43.4K 1.82%
Annual Population Growth

King County Population

Demographics

Economics and Income Statistics