Welcome to FT and to the Pacific NW! Make sure you check out Community as we usually have a monthly dinner meeting with each other; hopefully you can join us!

As others have said, Alaska has the most frequent service from SEA but I fly UA most often since they have more service to cities east of the Cascades. If you decide to go with AS make sure you sign up for their VISA card - it's excellent and Bank of America has a AS debit card that allows you to earn miles as well. AS has a great ff program with the 1/2 off mileage awards as well as their code share with CX. If you have any questions re: Seattle you can always PM (private message) me.