Washington state’s population has been on a steady increase for several decades.
It passed 8 million in 2024, according to the Washington State Office of Financial Management, and projections expect the state population will exceed 9.8 million by 2050.
But where is this growth occurring most? You might think it’s all in Seattle, but Washington’s population growth spans the state.
New data from the Census Bureau shows that there has been growth in nearly every county.
Only two counties had a decrease in residents, Island County (381 fewer residents) and Walla Walla County (519 fewer residents).
Since April 2020, Washington’s total population has increased by 250,594 people. More than 100,000 of them came to Washington between July 2023 and July 2024.
The number of new residents and percentage change are included for July 2023 to July 2024, as well as change between April 2020 to July 2024. These are determined by adding the population base to the number of births in a given location, plus migration rates and subtracting the number of deaths.
King County had the most new residents from July 2023 to July 2024, with 43,398. The second-most was Snohomish County, with 13,816 new residents. This is less than a 2% increase for both counties.
Okanogan County had the highest population increase by percentage at 2.1% with 944 new residents.
Since 2020, King County has brought in the most new residents by sheer numbers with 70,545 new residents. Snohomish County saw 36,158 new residents, Clark County saw 23,961 new residents and Pierce County had 20,008.
Population growth in Washington has been happening across the state.
From July 2023 to July 2024, here’s how much these eastern and western Washington counties grew:
Several other counties have had a significant increase in population since 2020:
© 2025 Tri-City Herald (Kennewick, Wash.). Visit www.tri-cityherald.com. Distributed by Tribune Content Agency, LLC.
