2020 Census Results: Here's How King County Grew

KING COUNTY, WA — The 2020 Census has released its final results, showing how communities across Washington are divvying up the state's massive population boost.

“We are excited to reach this milestone of delivering the first detailed statistics from the 2020 Census,” said acting Census Bureau Director Ron Jarmin. “We appreciate the public’s patience as Census Bureau staff worked diligently to process these data and ensure it meets our quality standards."

According to the data, from 2010 to 2020 Washington's population grew 980,741 people — about 14.6 percent — to 7,705,281 residents. Washington grew at almost twice the rate of the rest of the nation: the U.S. on the whole saw a 7.4 percent population growth.

Census data also gives some insight into Puget Sound's ongoing housing and homelessness crisis: while the state population grew 14.6 percent, available housing only grew 11 percent over the past decade.

That Washington saw an explosion in growth is probably not too surprising to hear, especially if you live in or around Puget Sound. The Census' population density map gives a clear idea of just how much that growth was centered in Western Washington.

King County saw the largest population growth, swelling 17.5 percent to 2,269,675 residents. Neighboring Snohomish and Pierce counties were not far behind: Snohomish grew 16.1 percent to 827,957 residents, and Pierce grew 15.8 percent to a population of 921,130. Thurston County also fared well, growing to 294,793 residents for a 16.9 percent growth.

Together the Seattle metropolitan area, including all of Pierce, King and Snohomish counties, ranked as the 15th largest metro in the country. Inside the metro, Kent grew the fastest, and was listed as one of the 10 fastest-growing cities in the entire country, the Seattle Times reported.

Of Washington's 39 counties, only two saw their population's decline: Columbia County, where the population dwindled 3.1 percent to 3,952, and Ferry County, which shrank 4.9 percent to 7,178 residents.

The shrinking in those smaller counties and growth in Puget Sound mirror national trends, which showed metro areas outpacing rural ones in growth. The population of U.S. metros grew 9 percent from 2010 to 2020. By 2020, 86 percent of the country's population lived in metros, versus 85 percent a decade prior.

“Many counties within metro areas saw growth, especially those in the south and west. However, as we’ve been seeing in our annual population estimates, our nation is growing slower than it used to,” said Marc Perry, a senior demographer at the Census Bureau. “This decline is evident at the local level where around 52% of the counties in the United States saw their 2020 Census populations decrease from their 2010 Census populations.”

Here's a look at the growth of several King County cities: