How to remove tax from a total
- Find the combined rate. Look up the total sales tax rate where you bought it — for example 13% in Ontario or 14.975% in Quebec.
- Divide the total by 1 plus the rate. Divide the tax-included total by 1.13 (Ontario) or 1.14975 (Quebec). The answer is the price before tax.
- Subtract to get the tax. Subtract the price before tax from the total. What is left is the tax you paid.
Type your total into the Total line of the receipt above and the price before tax and each tax fill in. You can also type the tax amount from a receipt to find the price it was charged on.
Divide by this number in each province
The divisor is 1 plus the combined rate. The last column shows a $100.00 total worked backwards.
| Province or territory | Rate | Divide by | $100 total → before tax |
|---|---|---|---|
| Alberta | 5% GST | 1.05 | $95.24 + $4.76 tax |
| British Columbia | 12% GST + PST | 1.12 | $89.29 + $10.71 tax |
| Manitoba | 12% GST + RST | 1.12 | $89.29 + $10.71 tax |
| New Brunswick | 15% HST | 1.15 | $86.96 + $13.04 tax |
| Newfoundland and Labrador | 15% HST | 1.15 | $86.96 + $13.04 tax |
| Northwest Territories | 5% GST | 1.05 | $95.24 + $4.76 tax |
| Nova Scotia | 14% HST | 1.14 | $87.72 + $12.28 tax |
| Nunavut | 5% GST | 1.05 | $95.24 + $4.76 tax |
| Ontario | 13% HST | 1.13 | $88.50 + $11.50 tax |
| Prince Edward Island | 15% HST | 1.15 | $86.96 + $13.04 tax |
| Quebec | 14.975% GST + QST | 1.14975 | $86.98 + $13.02 tax |
| Saskatchewan | 11% GST + PST | 1.11 | $90.09 + $9.91 tax |
| Yukon | 5% GST | 1.05 | $95.24 + $4.76 tax |
Frequently asked questions
How do I calculate tax backwards from a total?
Divide the total by 1 plus the tax rate as a decimal. With 13% HST, $226 ÷ 1.13 = $200 before tax, so the HST is $26.
Why can’t I just take 13% off the total?
Because the tax was calculated on the smaller, pre-tax price. 13% of $113 is $14.69, but the HST in $113 is only $13.00. Dividing by 1.13 gives the right answer.
How do I remove GST and PST separately?
Divide the total by 1 plus the combined rate to get the price before tax, then multiply that price by each rate. In B.C., $224 ÷ 1.12 = $200, so GST is $10 (5%) and PST is $14 (7%).
What if the reverse calculation is off by a cent?
Stores round tax to the nearest cent, so working backwards can land a cent away from the original price. This calculator keeps your total exactly and puts any rounding cent in the tax.
Related tools
Sources
Checked against these official sources on . How we calculate
- GST/HST calculator (and rates) — Canada Revenue Agency
- RC4022 General Information for GST/HST Registrants — Canada Revenue Agency