Do parking garage stalls, on average, cost $40,000 each to build in the Seattle area?

At least. That $40,000 per-stall number comes from a 2014 UCLA study. 

A 2026 update of that same UCLA Institute of Transportation Studies study in February 2026 shows underground construction now averages $73,000 per space. Portland has the most expensive underground parking stalls at $111,000 per space. Above-ground structures cost $99,000 per space in Portland. (Phoenix stalls are at the low end, at $29,000 each.)

According to this data, Seattle ranks fourth highest behind Portland, San Francisco and Minneapolis for underground parking and third highest for above-ground structures. 

Underground parking mandates can raise office building costs 68% and shopping center costs 70%

An average parking stall is 180 square feet, which researchers point out could otherwise be used for housing. Because housing is at a premium in metropolitan cities, that space becomes nearly as valuable as housing.