I am traveling from SF to Seattle (Alaskan) to take a BA flight back to the UK, I am not a US citizen. Can I safely make the flight if I allow two hours to get from domestic to international with my bag? My other option is a 7 hour wait! :(
Unlike terminal transfer at Heathrow there's no time wasted waiting for an airside bus between terminals, and the little shuttle trains that link to the S and N satellites are quick. Most but not necessarily all flights to the UK are from S gates. You won't have to pass through US immigration and customs arriving from SFO which saves more time. If you have checked bags, allow up to 30 minutes from arrival to pick them from the carousel. In the past I have had to go through security at SEA when connecting through Seattle from a pre-cleared Canada-US flight to a US-UK flight, but not the last few times between domestic US and US-Canada flights. Bottom line is that 2 hours should be OK even with checked bags.