Washington State Population Growth By Counties & Cities In 2023

No Washington county lost population this year, but a few in Eastern Washington had a 0% growth rate: Garfield, Ferry and Columbia. The fastest-growing county was Whatcom, where Bellingham is located, which grew around 1.8%. Benton County, where Kennewick is, had the second-fastest growth rate at about 1.5%. Snohomish County came in third, just shy of 1.5%. Four cities in Snohomish County had major growth rates: Mountlake Terrace (7.9%), Sultan (7.5%), Lynnwood (5.3%) and Monroe (4.5%).