When you pay for gas at the pump, a significant share of the amount goes neither to the retailer nor to the oil company: it’s taxes. In Quebec, several stack up on the same litre — two sales taxes, a specific fuel tax, a federal excise tax and the cost of the carbon market. Here’s what each one represents, who collects it, and why the tax portion stays relatively stable while the posted price keeps moving up and down.
The two sales taxes: GST and QST
Like almost everything you buy in Quebec, gasoline is subject to two sales taxes. The GST (goods and services tax) is a federal tax of 5%. The QST (Quebec sales tax) is a provincial tax of 9.975%. Together they make a combined rate of 14.975%, collected by merchants and remitted to the governments.
A detail that’s often misunderstood: since January 1, 2013, the QST is no longer calculated “on top of” the GST. The two taxes apply separately to the same price rather than one on the other — the famous “tax on tax” was abolished on that date, and the QST rate was adjusted to 9.975% to compensate (Revenu Québec). On the other hand, the sales taxes do apply to a price that already includes the fuel tax and the carbon cost — so you really do pay sales taxes on those other components.
Quebec’s fuel tax
This is the tax specific to gasoline, collected by Revenu Québec. Unlike the GST and QST, which are percentages, it’s a fixed amount per litre: 19.2 ¢/L for gasoline, a rate in force since April 1, 2013 (Revenu Québec). Because it’s fixed per litre, its relative weight grows when gas prices fall and shrinks when they rise.
Why it isn’t the same everywhere
The rate isn’t uniform across the province: some regions get reductions. Two mechanisms coexist.
- Peripheral and specific regions: since 1985, a reduction has applied to territories far from the major centres, to account for higher supply costs.
- Border regions: a reduction applies near the borders, to keep motorists from simply crossing to the other side to fill up. It ranges from 3 to 12 ¢/L near the U.S. border and from 2 to 8 ¢/L near Ontario and New Brunswick (Quebec ministry of Finance).
This is one of the concrete reasons the posted price changes from one region to another — you can see the differences live on the average prices by region page, or in our Montreal vs Quebec City comparison.
The federal excise tax
The federal government also levies an excise tax on gasoline, set at 10 ¢/L (Natural Resources Canada). Like Quebec’s fuel tax, it’s a fixed amount per litre, built into the price before the sales taxes even apply.
The carbon cost: Quebec’s cap-and-trade market
Quebec has its own approach to carbon pricing: the cap-and-trade system for emission allowances (SPEDE, by its French acronym), in place since 2013 and linked to California’s market. Rather than a direct tax at the pump, the system requires fuel distributors to buy emission allowances; that cost then flows through into the price of gas.
A stable share of a moving price
The takeaway: the tax portion of your fill-up is largely fixed and predictable. The per-litre amounts (fuel tax, excise tax) don’t change from day to day, and neither do the GST/QST rates. What makes the posted price swing is the market component — crude oil, the wholesale price and the retailer’s margin. To time that moving part, see our guide on the best time to fill up, and follow the market share in real time by comparing average prices by region.
Frequently asked questions
Do you pay QST on top of GST on gas?
No. Since 2013, QST and GST apply separately to the price, with no “tax on tax”. That base price does, however, already include the fuel tax and the carbon cost, so the sales taxes genuinely apply to those components.
Why is gas cheaper in some border regions?
Because Quebec’s fuel tax is reduced there, from a few cents to more than ten cents per litre depending on the border. The reduction aims to keep Quebec motorists filling up on this side of the border rather than driving across.
Does Quebec have a “carbon tax” like other provinces?
Not in the same form. Instead of a federal charge at the pump, Quebec applies its cap-and-trade carbon market. The cost exists, but it flows through fuel distributors rather than appearing as a separate tax line on your bill.