Canadian · Sales Tax
Reverse HST calculator, Ontario.
Got a total with tax already in it? Enter it and get the price before tax and the HST that was added.
In Ontario the combined rate is 13% HST. To remove it, divide the total by 1.13. Example: $339.00 ÷ 1.13 = $300.00 before tax, so $39.00 of the total is tax.
Inputs
Result
Enter a total to see the price before tax.
How the reverse calculation works
Ontario charges one harmonised tax of 13%. The CRA table lists it as a single GST/HST rate with no separate provincial column, so there is only one tax line to back out.
Pre-tax price = total ÷ 1.13. Tax = total − pre-tax price. Worked examples at the Ontario rate:
- $339.00 total = $300.00 before tax and $39.00 HST.
- $56.50 total = $50.00 before tax and $6.50 HST.
Ontario totals, tax removed
| Total paid | Before tax | HST |
|---|---|---|
| $10.00 | $8.85 | $1.15 |
| $25.00 | $22.12 | $2.88 |
| $50.00 | $44.25 | $5.75 |
| $100.00 | $88.50 | $11.50 |
| $250.00 | $221.24 | $28.76 |
| $500.00 | $442.48 | $57.52 |
| $1,000.00 | $884.96 | $115.04 |
Sources, read October 2026: CRA, GST/HST rates by province (calculator page) (page details 2026-04-08). Rates change; the CRA page above is the one to check.
Frequently asked questions
How do I remove HST from an Ontario total?
Divide the total by 1.13. That is 1 plus the combined rate of 13%. The result is the price before tax; subtract it from the total to get the tax. $339.00 ÷ 1.13 = $300.00, so the tax is $39.00.
Why can't I just take 13% off the total?
Because the rate applies to the pre-tax price, not to the total. Taking 13% of $339.00 gives $44.07, but the real tax is $39.00. Dividing by 1.13 is the correct reverse.
Is the HST in Ontario 13% on everything?
No. 13% is the general rate. Some supplies are zero-rated (0% across Canada, per the CRA) or exempt, and some items carry a different rate by law, so a receipt with no HST line should not be divided by 1.13. Use the custom-rate box to try another rate, or read the tax line printed on the receipt.
Will the answer match my receipt to the cent?
Usually, but not always. A seller rounds the tax on its own invoice, sometimes line by line, and more than one pre-tax price can produce the same total once rounded. This tool rounds the pre-tax price to the nearest cent and makes the tax lines add back to your total. If the receipt prints the tax, trust the receipt.
Estimate only
This is arithmetic on the rate you choose. It does not know whether the items you bought were taxable, zero-rated, exempt or taxed at a different rate, and it does not look anything up from the CRA or any provincial register. Where a receipt prints its own tax lines, use those. Verify current rates with the CRA before invoicing.