SEA Airport proposes new terminal, 19 gates in massive expansion plan

The Seattle-Tacoma International Airport (SEA) is proposing a group of expansion projects that include a new terminal.

The Federal Aviation Administration (FAA) completed a Federal Environmental Assessment for the 31 proposed plans, the Port of Seattle annnounced.

Multiple new projects approved for SEA

Included in the 31 proposed projects are a second terminal with 19 new gates, a ground transportation center, off-site cargo facilities, extensions of airfield taxiways, and an expansion of the fuel facility in preparation for future fuel needs.

A specific goal of the project is to accommodate increasing passenger demand of 56 million individuals and cargo through 2032. If approved, these projects would be completed or under construction by 2032.

Port of Seattle noted the Federal Environmental Assessment is one step in a continued effort to evaluate all 31 projects.

Next steps include a community review process, meetings, and a potential public comment period, before a decision is made on whether to approve the expansion.

Passengers claim SEA is overcrowded

Capacity issues dating back to 2019 have caused long TSA wait times and travelers standing in lines that stretched as far as the airports parking lots, according to KIRO 7.

“I think we’ve outgrown this airport,” said Herbert Edwards, a long-time traveler through SEA.

The managing director at SEA, Lance Lyttle, previously stated his concerns of overcrowding back in 2023.

“If you come to the airport any time during peak, especially during the summer, you’ll see lines going outside the building,” Lyttle said.

Study finds SEA struggles with customer satisfaction

A survey from the consumer research firm J.D. Power ranked SEA as the 17th mega airport — 33 million passengers or more each year — out of 20 total airports. The study conducted surveys of 30,000 airport passengers between July 2024 and July 2025.

SEA tallied a below-average customer experience rating for the eighth-straight year, according to J.D. Power. While the airport’s overall service and timeliness of flights received positive feedback, SEA received the most criticism regarding its issues with overcapacity.

Delta adds service to Seattle

Popular airliner Delta announced it will add more service to Seattle with a daily nonstop route between Seattle and Philadelphia, according to KIRO 7.

“Philadelphia has been a top-requested destination from our Seattle corporate customers, and this new service reflects our commitment to investing in the routes that matter most to them while building an even stronger network from the Pacific Northwest,” said Amy Martin, Vice President of Network Planning at Delta Air Lines.

The changes are expected to be implemented on May 7, 2026.

“Seattle continues to be one of Delta’s most important coastal gateways, connecting customers to key business and leisure destinations across the country and around the world,” Martin said.

This story has been updated and republished.

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