The 2.6km line will extend the Link light rail south beyond the existing terminus at Seattle-Tacoma International Airport on an elevated alignment along 28th Avenue South to Angle Lake station on South 200th Street in SeaTac. The new terminus will be a park-and-ride station with up to 1100 parking spaces.

The €US 383.2m extension is due to open in September 2016 and is expected to carry around 25,000 passengers per day with peak services operating at six-minute intervals between SeaTac and University of Washington. The opening of the line will reduce the journey time between South 200th Street and the city centre by 19 minutes, and to the University of Washington by 27 minutes.

The extension is expected to eliminate 41 million-km of car journeys each year in the Interstate 5 corridor.