How the figures are built

Every price on this site starts from an official publication, read by a script that runs every day (October 26, 2026 for this edition). Nothing is reported by users, nothing is copied from another price site, and nothing you type in a calculator leaves your browser. This page sets out the sources, the estimate for tomorrow, how its error is measured, how taxes are rebuilt and what is left out.

The official sources

• Government of Ontario weekly survey: self-serve averages of regular, premium and diesel in 14 markets, collected on Mondays (latest October 19, 2026). Toronto is the mean of Toronto West and Toronto East; Mississauga and Brampton use Toronto West, Oshawa Toronto East, and Hamilton, Kitchener-Waterloo and Barrie the southern Ontario average, because Ontario publishes no figure of their own. Open Government Licence – Ontario.
• Régie de l’énergie du Québec daily survey: average posted price of regular gasoline by region and sub-region, every weekday morning (latest October 26, 2026). The Régie publishes no reuse licence, so the site shows one dated figure per city with its source and never reproduces the table. Its history is read at build time to compute the estimate; it is neither stored in the site's code repository nor published.
• Atlantic regulators: maximum self-serve prices set by the Nova Scotia Energy Board (Zone 1 for Halifax), the New Brunswick Energy and Utilities Board (one maximum for the province) and the Newfoundland and Labrador Board of Commissioners of Public Utilities (Zone 1 for St. John's). These are public orders, quoted with their effective date.
• Statistics Canada table 18-10-0001-01: monthly average pump prices in 18 cities (latest September 2026), used for the West, for premium and diesel in Quebec and the Atlantic, and as a monthly reference. Open Government Licence – Canada.
• Government of Ontario wholesale prices: daily rack prices for Toronto, Thunder Bay and Edmonton, published with about a week of delay (latest October 21, 2026).
• Natural Resources Canada 2026 fuel consumption ratings: median combined consumption by vehicle class, for the budget calculator.

Natural Resources Canada's weekly city averages are not used: its price pages are covered by terms that forbid commercial redistribution without written permission.

The estimate for tomorrow

Estimate = latest official price + market movement since that price × (1 + sales tax rate) + dated tax changes between the two dates, sales tax included.

Market movement has two parts. First, the change in the rack price of the region (Toronto for Ontario, Quebec and the Atlantic, Edmonton for the Prairies and British Columbia) between the days before the survey and the last three days published before tomorrow. Because Ontario publishes rack prices about a week late, this part is usually empty for a weekly or daily survey. Second, for gasoline in Ontario, Quebec and the Atlantic, the change since then in the Régie de l'énergie's Montréal-region survey once GST, QST, Quebec fuel tax, the regional transit tax and the federal excise tax are removed: a pre-tax market signal published every morning. Diesel has no daily open signal, so its estimate moves only with rack prices.

For a monthly Statistics Canada average, the reference is the month's average rack price, and the dated tax changes include those since mid-month: Alberta's September price, which included 13 cents of provincial fuel tax, is brought down by 13 cents plus GST from October 1, 2026. For an Atlantic maximum price, nothing moves on a day when the regulator does not reset it (Fridays in Nova Scotia and New Brunswick; every day for now in Newfoundland and Labrador).

The error, measured

For each city and fuel, the method is replayed over past surveys: from each survey it estimates the next one using only what was published the day before, rack prices with a week's delay included, and the absolute gap with the actual figure is averaged. The same is done for a naive "no change" guess. Weeks or months that straddle a tax change the method does not model (the end of the federal carbon charge on April 1, 2025, for instance) are left out of both measures. In Toronto, over 140 weeks, the method missed by 2.4¢/L on average, the naive guess by 3.8¢/L.

Taxes per litre

The provincial fuel tax and any regional tax come from each province's official page (Ontario, Quebec, British Columbia, Alberta, Newfoundland and Labrador, Nova Scotia) and from Natural Resources Canada’s table of fuel levies. The federal excise schedule comes from Finance Canada and its September 2026 draft legislation. GST, HST or GST plus QST applies to the price including those taxes, so the price before sales tax is the pump price divided by one plus the rate. What is left after all taxes is the refined product, transport and margins.

What is left out

Single stations: the site shows averages and ceilings, never a price at a given station. Kelowna and other cities with no official average of their own: their page gives the taxes and a calculator for the price you see. Full-serve, mid-grade and delivery charges in New Brunswick. Taxes in the territories, which no city page covers. Quebec's lower fuel tax near the borders is applied to Gatineau only (6 cents within 15 km of Ontario, per the Régie's zone indicators of February 24, 2026).

Checks

Before each release, automated tests check the excise calendar, the estimate on worked examples, the Alberta tax pause, the exclusion of unmodelled tax changes from the error measure, the tax breakdown and the fill-up and budget arithmetic. The data script stops a source that returns an outage page instead of data and keeps its previous file, so a page always shows the last date actually read.