Originally Posted by
Duke787
Assuming you are connecting onwards yes. All of SEA is connected airside (though you may have to take the airside trains if going to "North" or "South" terminal -- and I believe AS mainline does fly out of North on occasion) so once you clear immigration and check back into your AS flight and pass through security you'll be able to access the UC + "The Club at SEA" and anything else you want to explore.
The UA lounge is over in Terminal A, I don't think AS departs from A gates (they depart from almost everywhere but A) but it'll be easy enough to walk over, just make sure you leave yourself enough time from the UC to your eventual departure gate -- especially if you end up needing to take the train to "North"
I did this once a few years back, I still had my UC membership but had switched over to AA and was doing a MR to SEA and ended up killing time in the UC -- was easy enough.
Very helpful, thanks.
UA has let me in once before in a similar situation (arriving on a J flight from overseas, but connecting with another carrier) though I suspect it's up to the managers discretion and how busy they are. I would have flown them all the way through but they don't even have decent flights with connections to SEA to/from AUS much less direct. Alaska has direct flights but only 2 a day, hence the long layover. The UA flights w/connections would actually get us home later even with a shorter stop at SEA.
We're meeting family in Seattle for a couple days on the way out, hence flying to Japan from there (plus ANA is just better than UA for J class) and also why doing another short day trip in Seattle on the return isn't appealing.