International travelers passing through Seattle will soon have a different experience passing through the S Concourse at Seattle-Tacoma International Airport (KSEA). According to officials from the Port of Seattle, the concourse will be getting a $2.5 billion renovation, transforming the 1973-era facility into a more modern space. Work is slated to begin in 2027.
“Today’s authorization to move forward with the S Concourse Evolution builds on the generational investments we are making at SEA to improve the passenger experience,” Port of Seattle Commission President Ryan Calkins said in a statement. “The project will add critical seismic, structural, and building systems upgrades to improve long-term passenger circulation as well as operational efficiency.”
The plans do not include adding more gates because there isn’t sufficient room to expand between the main terminal and the airfield. Instead, the plan calls for repurposing the former customs area that was vacated in 2022 when the International Arrivals Facility opened.
Airport officials said the remodel will add 150,000 square feet to the facility, including a new Upper Concourse Level, improved dual-level boarding operations for select gates, and an increase in options for dining and shopping, in addition to more passenger lounges.
The present building was designed more than 50 years ago, and passenger needs have evolved, said SEA Airport Managing Director Wendy Reiter.
“The existing building is over half a century old, making it challenging for us to meet our goals of providing the best possible service to our travelers and tenants—this is a necessary upgrade,” she said. “As we’ve done in previous Upgrade SEA projects, we’re being innovative by building up and not out. We’re mindful of the fact that we have one of the smallest footprints of any major U.S. airport considering our passenger volume.”
“The design solution for the S Concourse Evolution project carefully balances required resiliency improvements to the existing structure and systems, increased efficiency for aircraft operations and building services, and modernization of the interior to enrich the traveler experience,” said Kevin Keady, AECOM West Region business leader of Buildings + Places. “The design is inspired by local, indigenous concepts combined with pragmatic enhancements that will achieve greatly improved passenger service levels and meet the high standards travelers are accustomed to at one of the world’s busiest airports. We are grateful for the opportunity to work with SEA airport on this exciting project that will benefit the region for the next 50 years.”
The Process
According to Port officials, the project will be completed over the next eight years so as not to disrupt flight operations or create inconvenience for travelers. The goal is to have only three of the 12 gates impacted by construction at any time.
In order to make up for the gate closures, a temporary S Annex east of the facility will be built to support ground boarding operations.
The goal is to have the project completed by 2034.
Construction began on Seattle-Tacoma International Airport in 1942 at Bow Lake just north of what is now King County Airport Boeing Field (KBFI). Community leaders realized that landlocked KBFI had very little room for expansion because of the Boeing plant and local neighborhoods. In addition Bow Lake sat an elevation of 423 feet msl as opposed to KBFI at 17 feet. The higher field elevation makes KSEA less susceptible to fog, which hampered flight operations as instrument flight as we know it today was still in its infancy.
The first runway was completed in 1944. Commercial air service began in 1947, with the first passenger terminal opening in 1949.
Today the airport has on average approximately 55 international flights departing each day. Multiple airlines offer nonstop flights to Asia, Europe, Mexico, Canada, and the Middle East.