The 800-mile flight between San Francisco and Vancouver, British Columbia is a startling expensive airline ticket much of the year. For May and June travel there is a relatively low $226 round trip ticket SFO-YVR Vancouver flying either Air Canada or United-operated flights marketed as Air Canada codeshares. These are nonstop flights.
Air Canada currently offers $226 round trip airfare every Tuesday and Wednesday in May and June 2016. United Airlines tickets are $365 to $385 for same flights. You need a minimum six nights to get the lowest fare, but the price is only $30 to $40 more to return on some other day of the week if six nights is too long.
Alaska Airlines has a few Tuesday dates in May at $256 round trip. Most Alaska Airlines fares for SFO-YVR are in the $300s like United Airlines.
Air Canada ticket for United Airlines operated flights
San Francisco SFO – Vancouver YVR (nonstop flights)
Wednesday June 15 – Wednesday June 22
$225.63 round trip
Air Canada A booking code earns 50% United Mileage Plus flight miles for 800 frequent flyer miles on SFO-YVR round trip. Air Canada Economy A code ticket earns 100% EQM and segment credit.