Seattle-Tacoma International Airport (SEA), like the greater region, experienced unprecedented growth in the last decade. In 2024, traveler volumes surpassed the pre-pandemic highs. To meet current and forecasted traveler demand, there’s a massive modernization and construction program happening before your eyes called Upgrade SEA. These capital improvements will benefit our region and improve the travel experience for decades to come. While construction can be disruptive, it’s essential to continue to invest in the future of SEA Airport.
Completed capital projects in the Central Terminal, N Concourse, and International Arrivals Facility have created or modernized approximately one million square feet; however, many remaining airport facilities were built for fewer passengers and older building standards and still need the Upgrade SEA treatment.
Upgrade SEA projects will elevate the traveler experience from drives to curb to gate, and meet the future needs of our region by:
- reducing congestion in the terminals and on the drives
- improving the traveler experience
- incorporating sustainability practices and technology
- facilitating accessibility and equity
- creating more space for travelers, tenants, and Airport Dining and Retail
- upgrading building facilities
What’s happening at SEA?
You’ll notice construction and progress on these projects in 2025.
SEA Gateway Project
SEA Airport is building a better front door with the SEA Gateway Project. A completely new vision for the Alaska Ticketing area will create a beautiful, welcoming space; use updated technology to improve the check-in and bag drop process; and redesign checkpoint 5.
C Concourse Expansion
The C Concourse Expansion will transform the airport by raising the existing roof and adding four additional floors and over 100,000 square-feet of dining and retail, and a light-filled performance space. The highlight will be a glass overlook with unobstructed views of the mountains and the airfield, called the Lookout at C.
S Concourse Evolution
The S Concourse Evolution project brings a new vision to the 40-year-old S Concourse to modernize and renovate the facility with modernized building systems, seismic updates, design updates that prioritize comfort, and more restaurants and shops that make you feel at home.
Concourse A Building Expansion for Lounges
This project is adding a new facility to the end of the A Concourse with updated and new premier lounge space. An expanded Club at SEA will anchor the new building, while Delta will have premier lounge space above. This new building adds approximately 52,000 square feet for more room to roam and more services.
Checkpoint 1 Relocation
The Checkpoint 1 Relocation project is creating a brand-new TSA Security Checkpoint on the Baggage Claim Level. With more capacity to screen more travelers, you’ll also get an improved queueing system and beautiful artwork.
