Sea-Tac’s long-running terminal overhaul just got a lot more real. The C Concourse expansion has shifted from bare-bones steel to something that actually looks like an airport, with crews installing glazing, mechanical systems and finish work across the upper floors. Port officials are still aiming to have the project substantially complete in time for the 2026 FIFA World Cup, which kicks off on June 15, 2026.
A March 10 early-look video gives travelers a first peek at the new multilevel atrium and food hall circulation. As KING 5 reports, the preview shows crews setting windows, finishing out corridors and testing mechanical systems while the concourse is readied for World Cup operations.
What’s Changing At Concourse C
The expansion stacks four new floors on top of the existing C Concourse, boosting the footprint from roughly 81,000 square feet to about 226,530 square feet and organizing the space around a tiered marketplace anchored by an amphitheater called the Tree at C. According to The Port of Seattle, the project will bring in new dining and retail, a more-than-20,000-square-foot Alaska Airlines lounge, office space for airport partners and a glassed lookout with direct airfield views. The Port also highlights sustainable touches such as rooftop photovoltaics and electrochromic glazing, and it continues to project substantial completion in the second quarter of 2026.
Who’s Building It And The Price Tag
Turner Construction is the general contractor on the roughly $399 million expansion, which hit a topping-out milestone late last year when one of the final steel beams was set in place. Miller Hull and Woods Bagot are the design partners, and industry coverage has detailed the careful choreography required to add deep foundations and new vertical structure while the surrounding terminal stays open. Construction trade reporting notes that the project is expected to be largely complete between May and June 2026, with airport teams then wrapping up interior fit-out and tenant build-outs, according to Construction Equipment Guide.
What Travelers Should Expect
Once Concourse C opens, travelers can look for a multilevel marketplace, more seating and a mix of new dining options that emphasizes local flavors alongside the usual national names. Axios reports that airport leaders are phasing visible finish work and roadway upgrades so that key areas are ready before the June 15, 2026 tournament kickoff. The catch is that you may still walk past active work zones while new shops and seating areas are opening, so it is wise to budget a little extra time to find your way around.
Local outlets have been tracking this broader construction wave for months, and the broader UpgradeSEA push got a rundown in January that flagged Concourse C as one of several major projects set to reshape the terminal. With the early-look video now out and interior work still in full swing, Sea-Tac is expected to keep bringing portions of the concourse online through the spring and into early summer.
