Enter the total price you paid (tax included) and your province — we'll extract the exact pre-tax price and tax amount.
Some items like basic groceries are GST/HST zero-rated. Prescription drugs and most medical devices are also exempt. Children's clothing, books, and feminine hygiene products are zero-rated federally but may be subject to provincial tax in some provinces.
Combined GST/HST + PST/QST rates by province
About reverse GST/HST calculation in Canada
The formula is: Pre-tax price = Total ÷ (1 + tax rate). For Ontario's 13% HST: pre-tax = $113 ÷ 1.13 = $100. The tax amount is simply the total minus the pre-tax price: $113 − $100 = $13. This works for any combined rate.
Quebec charges both GST (5%) and QST (Quebec Sales Tax at 9.975%). However, QST is calculated on the pre-GST price — not on top of GST. So the combined rate is 5% + 9.975% = 14.975%, not compounded. This makes Quebec's effective rate the same as New Brunswick, Nova Scotia, Newfoundland, and PEI at about 15%.
Zero-rated items (0% tax): basic groceries, prescription drugs, most medical devices, feminine hygiene products, diapers, most farm products. Exempt items: most healthcare, educational services, financial services, residential rent. Some provinces apply PST to items that are federally zero-rated — for example, BC applies PST to some snack foods.
HST (Harmonized Sales Tax) is a single combined federal+provincial tax collected together — used in Ontario, New Brunswick, Nova Scotia, Newfoundland, and PEI. GST+PST provinces (BC, Manitoba, Saskatchewan, Quebec) collect the federal GST and their own provincial tax separately, though you pay both at checkout. Alberta, Yukon, NT, and Nunavut have no provincial sales tax — only 5% GST.
Extracting tax from a total price — the math explained
When you pay $113 at a store in Ontario, you're paying $100 for the item plus $13 in HST. But the receipt just shows $113. If you need the pre-tax price — for an expense report, a refund claim, or just to know what you actually paid — you need to work backwards.
The formula is simple: pre-tax price = total paid ÷ (1 + tax rate). For Ontario's 13% HST that's $113 ÷ 1.13 = $100. The tax amount is just the total minus the pre-tax price: $113 − $100 = $13.
The formula is the same regardless of which province you're in — only the rate changes. For provinces with GST + PST (BC, Manitoba, Saskatchewan, Quebec), both taxes are applied to the pre-tax price independently, so the combined rate is simply added together before dividing.
Quebec charges GST (5%) and QST (9.975%) separately, both applied to the pre-tax price. The combined rate is 14.975%. People sometimes think QST is applied on top of GST — it isn't. Both are applied to the base price, just collected separately. This calculator handles Quebec correctly.
About reverse GST/HST calculation in Canada
BC has a 12% combined rate (5% GST + 7% PST). Pre-tax price = $226 ÷ 1.12 = $201.79. The tax paid is $226 − $201.79 = $24.21, of which $10.09 is GST and $14.13 is PST. Use the calculator above — select BC, enter $226, and it will show the full breakdown instantly.
Basic groceries — bread, vegetables, meat, dairy, canned goods — are zero-rated for GST/HST purposes, meaning 0% tax applies. However "basic groceries" has a specific CRA definition. Snack foods, carbonated drinks, candy, chips, and restaurant meals are all taxable at the full rate. Some provinces also apply PST to items that are GST-zero-rated. Use the "Zero-rated / Exempt" option in this calculator for items like basic groceries.
If you are a GST/HST registrant (most businesses with over $30,000 in annual revenue must register), you can claim Input Tax Credits (ITCs) for the GST/HST you paid on business purchases. You need the supplier's GST/HST registration number and a receipt showing the tax amount. This reverse calculator can help you figure out exactly how much GST/HST was in a total price so you can enter the correct amount on your return.
Alberta has never had a provincial sales tax and has historically resisted introducing one due to strong public opposition. The province funds its government primarily through resource revenues (oil and gas royalties) and income taxes. Albertans only pay the federal 5% GST on most purchases, making it the lowest-tax province for consumption. This is one reason many Canadians choose Alberta for large purchases like vehicles and electronics.