Q: It is a different country, but Vancouver is by far the closest big city around. If you're going to call, say, Langley a suburb, then Blaine is actually closer.
A: Yes, but living in Blaine requires crossing the border. There is a fast lane for people who do it frequently, but it can be tedious. I suspect that employment data show that Blaine is a suburb of Bellingham with some people also working in Vancouver. It is like Snohomish in Washington, some people work in Seattle and some in Everett, but more work in the latter city so Snohomish is considered a suburb of Everett. Blaine is also a border town, and lots of its activity is a function of sitting at the main crossing from Washington into BC.