When Microsoft moved its campus to Redmond, Washington, in 1986, it was more of a suburb than its own city. Its population hovered between 20,000-30,000 people, and places now filled with condos and townhomes were vacant.
Today, its population has more than tripled from what it was 40 years ago and the city has grown alongside an Eastside tech corridor where thousands are employed. Recent data shows its population growth isn’t slowing down.
Among Seattle-area cities with at least 10,000 people, Redmond experienced the second fastest population growth from 2020 to 2023.
But it’s not just Eastside tech hubs experiencing such transformation. Lynnwood was the other major city that saw the fastest growth, adding 14% to its population. Other areas seeing fast growth are Edgewood, Arlington, Gig Harbor, Shoreline, and Bothell.
These demographic shifts have brought new businesses, transit connections, and diversity to each area. But it isn’t without its challenges.
Preparing for population growth
Seattle’s population growth has brought its own frustrations for both new and longtime residents. Housing prices, traffic congestion, and overall cost of living are among the growing pains.
Growth is not universal across entire counties, and some areas have experienced more rapid transformation than others. While some of this growth is from new arrivals settling in these cities, these changes can also reflect shuffling of long-term residents.
In Snohomish County, nearly 60% of movers from outside the county were still Washington state residents, and older county-level data suggests most are King County residents moving north. In King County, for comparison, just 26% of out-of-county movers were already living in Washington.
Washington enacted a law in 1990 to prepare for its rising population. The Growth Management Act requires municipalities plan for urban growth based on population projections while protecting important environmental and natural resource areas. Communities have to update their plans every 10 years, but population trends can shift at a faster cadence.
“There can be a lag between the needs of the population and the government infrastructure to take care of folks and have the needs prepared for them,” said Sara Curran, director of University of Washington’s Center for Studies in Demography and Ecology.
By the time investment in new schools and roads is complete for example, the school-age population may have grown more than projected or more residents may have unexpectedly moved to other parts of the county.
Smart planning can help cities prepare though. In Redmond’s case it recently updated its 2050 growth plan, updating zoning to support more multifamily development and new walkable centers clustered around light rail stations.
The boons of migration-driven growth
Transplants may add pressure to cities’ development plans, but their arrival also actively contributes to business growth and social services.
Like many other places in the U.S., the Seattle metro has seen a rapid increase in its 65+ population. Growth from migration refreshes the population and helps keep the region’s age structure more stable. Most movers to Seattle are between 20 and 40.
Immigration, especially from the working-age population, also brings a larger tax base to cities. While the state doesn’t have an income tax, increased consumer spending builds revenue for the region and also encourages new business.
“There's always a ripple effect for every new employee that comes to a place,” Curran said. “While there's a cost to their arrival, there's also a boon, subsequent spill over of the general generation of other dollars that lead to more businesses.”
Population growth in the Seattle region has both brought vitality to neighborhoods and suburbs and challenges for residents. In the 2010s, the city recorded steady gains from both domestic and international migration. But since the pandemic, domestic migration slowed, and growth became more reliant on international arrivals.
Despite this shift, the metro area still saw a 1.3% population increase from net migration, its highest since 2016, and it continues to outpace other West Coast cities in migration-driven growth. The region’s growth for the rest of decade may hinge on how federal policies impact international migration and whether Seattle again can attract domestic movers.
