transportation between Seattle and Vancouver, BC

There's a couple of busses that run daily from Seattle to Vancouver. I've never taken one, but they're apparently run by Flixbus, which could make for an interesting trip.

Good luck on your travels,

-- Mike Beebe

Mysticamper:

Greyhound bus: https://www.greyhound.com/

FlixBus: https://www.flixbus.ca/bus-routes/seattle-wa-vancouver-bc

If you use this transport mode, your arrival in Vancouver is at Pacific Central Station, which is also home to VIA cross-country and Amtrak international trains. The station is only 250 metres to Skytrain station “Main Street-Science World” on the Expo line, providing easy access into downtown Vancouver.

You can catch the Amtrak train from Seattle to Vancouver

You can catch the Amtrak train from Seattle to Vancouver

the OP said the Cascade train is fully booked. As noted there are bus options but you're going to be on the bus most of the day - shortest ride is 3.75 hours one way. Have you considered meeting each other half way? Bellingham is a good option, university town on the water.

Do you have a Passport or Enhanced Drivers license? Necessary for Crossing Border. A round trip in a day can be done, but you have to worry about getting back to train station or bus station ahead of time to go through Customs. Where does your friend actually live? "Vancouver" can include many other small towns. Maybe you can rendezvous if he is a Canadian used to crossing the Border. We see lots of Canadians shopping at our Costco.

Could you meet your friend in Victoria? The Victoria Clipper takes just as long as the train or bus, but it's a beautiful ride. It's the most expensive option, short of flying.
Bellingham, where I live, is an excellent place to visit. Getting here from Seattle without a car isn't as easy as one might hope, as we are limited to the same trains and buses previously mentioned. If you decide to meet here, DM me for recommendations on what to see and do and where to eat.

If you can tell us which area of Vancouver your friend is from, that would help.
It’s a very big area!
Meeting in Victoria is a good idea, as is Bellingham if your friend is happy to cross the border.
If your friend drives, could they come down to you?

Remember that border crossings may take up a bit of time nowadays.

Remember that border crossings may take up a bit of time nowadays.

Drove to BC in Jan. Took maybe 5 minutes each way. Depending on when you cross and which crossing you use, the line may be a bit longer.. The Canadian 'boycott" has had the benefit of making the crossing quicker.

Do you have any flexibility on the travel day to find a train ticket?

Meeting in Bellingham is a good alternative and is somewhere that you could drive to with out having to deal with Vancouver city traffic.

Even renting a care and driving will take at least 3 hours without considering traffic or border crossings, so everything else will take longer.

If it were me, I would take the Flixbus which takes between 3-4 hours and I would plan on spending the night in Vancouver to take the bus back the next day.

I went to Vancouver for the day on Thursday. We were in line for about 5 minutes going up, longer coming down (15?). Each time, there was only one booth open. "These days," this is typical.
If it's an option to stay overnight, I would take the train over the bus every time. What I understood was that the trains that are scheduled far enough apart to make it workable as a day trip are sold out. These will be the same trains that stop in Bellingham. IME, the Flixbus schedule is worse than Amtrak for same-day travel between Bellingham and Seattle, but maybe OP will have better luck going in the other direction.

I agree with other suggestions that you might want to stay at least one night in Vancouver. That would give you more time to visit with your friend and provide a more "relaxed" pace for the trip. There are some great hotels and restaurants in downtown Vancouver.

You might have a look at Harbour Air, which offers flights from Lake Union in Seattle to Vancouver Harbour. You'll have to be a bit more "adventurous" as the aircraft are smaller. You could book a hotel in the vicinity of Burrard & Georgia streets, or perhaps on Robson street. There are lots of choices. Take a Cab from the harbour to your hotel, as the harbour is reasonably close to the hotel area.

Good luck!

I wasn't aware of that flight from Lake Union. Only goes in the morning. If an afternoon train was available, that might work. Expensive.