Alaska Airlines, Delta, and United has round-trip flights from Seattle (SEA) to San Francisco (SFO) for $117-$137, NONSTOP. Flights September to November. Cheapest flights are on Tuesdays, Wednesdays, and Saturdays. Extended Weekends available. Origin/Destination reversible.
Carry-on bag is allowed for free on Alaska Airlines and Delta. You can avoid paying for seat selection by accepting the randomly assigned seat at the gate.
Note: United “Basic Economy” fares are cheapest ($117), but do not include a free carry-on bag. Only a personal item (like a small laptop bag) is free. Seats are randomly assigned for free prior to boarding. If you have the United MileagePlus credit-card, use the “free checked bag” perk.
Note: The personal item size on United flights is smaller (9-in/10-in/17-in) than Frontier or Spirit (8-in/14-in/18-in).


