Port of Seattle has completed the SEA Gateway Project, a $546 million renovation of the north end of the main terminal at Seattle-Tacoma International Airport.
The project modernized ticketing, security, and baggage claim areas within the 40-year-old terminal. Improvements include a new Alaska Airlines ticketing lobby, automated bag drops, upgraded baggage claim equipment, redesigned entry and exit doors, and a rebuilt security checkpoint at the north end of the terminal.
The Port of Seattle delivered the project in partnership with Alaska Airlines, which led design and construction as a tenant improvement. The design-build team included HOK and Hensel Phelps. The SEA Gateway Project carried a total cost of $546 million. Funding came from airport development funds and future airport revenue bonds.
Construction began in late 2022 and proceeded in phases. Phase A, which added check-in, bag drop, and employee office space, reached completion in 2024. Phase B, which reconfigured ticketing levels and expanded Security Checkpoint 6, reached completion in early 2026.
The renovated facilities improve passenger flow, increase screening capacity, and support higher passenger volumes. The upgrades benefit Alaska Airlines passengers, airport employees, and travelers using the airport’s north terminal.