Customs/Immigration transiting SEA from STL going to YVR questions

[quillwercruisers]

I tried to search, but couldn't find what I was looking for. First time transiting SEA, and I'm trying to find out what the procedure is in SEA when you are transiting there to fly into Vancouver. Will we go through any kind of customs/immigration at SEA? Is there separate domestic and international terminals? Will we have to go out of security and go back in?

 

Thanks in advance for any knowledge you can pass on.

[CruiserBruce]

Other than showing your passport to be eligible to fly into Canada, there is no Immigration or Customs procedure at SEA. Canadian Immigration and Customs will be when you land.

 

I don't know SEA's policy, but flights to nearby countries like Canada and Mexico don't have to go out of the international terminal.

[Ferry_Watcher]

Assuming that you are a US citizen, just make sure you are traveling with your passport book.

[quillwercruisers]

Yes, US citizens with passport. Thank you both for the information.

[princeton123211]

18 hours ago, quillwercruisers said:

Is there separate domestic and international terminals? Will we have to go out of security and go back in?

As others have said you are connecting domestically in SEA. There is an international terminal-- the S Gates-- but it's meant to service large widebody aircraft undertaking Transpacific and Transatlantic flights (think British Airways, Emirates, the occasional Hawaiian Airlines A330 flight). For a short hop to Vancouver you will most likely be departing from another domestic gate elsewhere (which isn't a bad thing-- the S terminal at Seatac is pretty bare bones compared to the others). 

[quillwercruisers]

Thank you!

[psuboater]

On 4/17/2024 at 4:32 PM, CruiserBruce said:

Other than showing your passport to be eligible to fly into Canada, there is no Immigration or Customs procedure at SEA. Canadian Immigration and Customs will be when you land.

 

I don't know SEA's policy, but flights to nearby countries like Canada and Mexico don't have to go out of the international terminal.

If you’re taking Alaska airlines, it looks like you’re in C gates like the other Alaska flights. Delta and Air Canada are departing from S gates. 
 

There’s a train to S gates which appears every 3-5 minutes. From a domestic connection there isn’t anything special other than getting to the South terminal. If you’re taking Delta you might have facial recognition at the gate  instead of scanning your passport, but have your passport with your ticket ready when boarding. 
 

Safe travels!

Edited April 19 by psuboater

[Ferry_Watcher]

We flew from Vancouver to Seattle and it was one of those small jets.  We deplaned on the tarmac and walked into the terminal.  I remember that my carry-on bag felt heavy as I walked down the narrow rollup stairs we used to exit the plane.  Luckily it was a shoulder bag and I could use my hands on the banister walking down the stairs from the plane.

[CruiserBruce]

@psuboater, I haven't flown internationally from SEA, that is why I said I don't know SEA's policy. But at SFO, have flown to Mexico (on United) and a couple Canadian airports, both on AC and UA, and left from domestic terminals. AC has several gates and a Maple Leaf Lounge in Terminal 2 at SFO, and that is a domestic terminal.

 

It seems the much longer haul flights need to use the International Terminal.

[princeton123211]

1 hour ago, CruiserBruce said:

It seems the much longer haul flights need to use the International Terminal.

The S gates in the international terminal aren't designed for the smaller 737s that make up most of the traffic at SEA. They're designed for larger widebodies flying to Asia and Europe which is why the Hawaiian A330s depart from the international terminal on a domestic routing. 

[psuboater]

1 hour ago, princeton123211 said:

The S gates in the international terminal aren't designed for the smaller 737s that make up most of the traffic at SEA. They're designed for larger widebodies flying to Asia and Europe which is why the Hawaiian A330s depart from the international terminal on a domestic routing. 

Yup, I was quite shocked myself when I looked it up on FlightAware. The only Canadian trip I've taken from SEA connected first in Detroit, so I had to look up previous gates.

[quillwercruisers]

Thanks everyone. We will be flying on Alaska Airlines.