Canadian vocabulary is pretty much the same as American, we say “gas”, not “petrol”, and use “I guess” instead of “I suppose”, but there are still some spelling holdouts, like “centre”, “theatre”, “colour” etc. But spelling of the “tire”, for example, is American, not British.

It's weird because the commonwealth countries all still insist on UK spelling, but have become much more American in their slang and actual speech.