Allegiant Airlines says it wants to pay for a terminal at Paine Field in Snohomish County.
The proposal would bring a total of 23 commercial flights per day to the airport between Allegiant and Alaska Airlines.
If Allegiant picks up the tab for the terminal, it could save the county money, but would give Allegiant full control of rates. Allegiant also expects to be paid back by receiving a portion of parking or passenger facilities charges.
Opponents to commercial flights at Paine Field say it would put a strain on Boeing and aerospace companies that also use the runway.
Real estate agents say there would be little to no impact on properties around Paine Field.
Flights from Paine Field would include routes to Portland, Spokane, Las Vegas and Hawaii.