It is true that gasoline can cost more up here but... it can be confusing when trying to compare prices.
Fuel is sold by the liter and not the US gallon, (1 US Gallon is about 3.78 liters). There is a difference in the $ exchange rate which changes all the time, currently $1.00 US costs us $1.325 Canadian. The price per liter for gasoline changes almost daily, not unlike many places in the US. Diesel, on the other hand, often costs slightly less than gasoline, at least recently here in Montreal. Taxes vary a lot between the various Provinces contributing to the price/liter differences. Currently in Montreal, gasoline prices are running between $1.14 to $1.20 per liter but has been up to $1.25 in recent weeks.
After all that: at $1.14 /liter, 1 US Gallon is costing about $3.28US
at $1.20/liter " $3.45US (in Montreal and if my math holds up!!!)