SFO > Seattle, Washington: $117 round-trip [SOLD OUT]San Francisco to Seattle, Washington: 3 night trip. Flight Options Flight Alone: $117. Dates we found this fare: Thu, Feb…...Details to this trip are for members only.Try it for 30 days for free. (We'll even send you a reminder before your first billing.) Already a member? Log in here (and be sure to check the "remember me" box.)Login problems? Click here.