Reverse HST Calculator — Find the Pre-Tax Price
Enter a tax-included total and select your province to extract the HST, GST, PST, or QST and find the original pre-tax price.
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Auto-tax on every invoiceReverse Tax Divisor by Province
Divide your tax-included total by this number to get the pre-tax price
| Province | Tax Rate | Divide By | $100 Total → Pre-Tax |
|---|---|---|---|
| Alberta, NWT, Nunavut, Yukon | 5% GST | 1.05 | $95.24 |
| Saskatchewan | 11% (GST+PST) | 1.11 | $90.09 |
| British Columbia, Manitoba | 12% (GST+PST) | 1.12 | $89.29 |
| Ontario | 13% HST | 1.13 | $88.50 |
| Quebec | 14.975% (GST+QST) | 1.14975 | $86.98 |
| NB, PEI, NL | 15% HST | 1.15 | $86.96 |
| Nova Scotia | 14% HST | 1.14 | $87.72 |
Reverse HST Examples — Ontario 13%
Common receipt totals with the HST and pre-tax price extracted
| Receipt Total | HST (13%) | Pre-Tax Price |
|---|---|---|
| $56.50 | $6.50 | $50.00 |
| $113.00 | $13.00 | $100.00 |
| $282.50 | $32.50 | $250.00 |
| $565.00 | $65.00 | $500.00 |
| $1,130.00 | $130.00 | $1,000.00 |
| $5,650.00 | $650.00 | $5,000.00 |
How to Reverse Calculate HST
Step 1: Find your province's combined tax rate
Look up the total tax rate for your province. Ontario is 13% HST. BC is 12% (5% GST + 7% PST). Quebec is 14.975% (5% GST + 9.975% QST). Alberta and the territories are 5% GST only.
Step 2: Divide the total by (1 + rate)
Convert the tax rate to a decimal and add 1. Ontario 13% becomes 1.13. Then divide: Pre-tax price = Total ÷ 1.13. For a $226.00 Ontario receipt: $226.00 ÷ 1.13 = $200.00 pre-tax.
Step 3: Subtract to find the tax
Tax = Total − Pre-tax price. From our example: $226.00 − $200.00 = $26.00 HST. This is the correct method. Do NOT multiply the total by 13% — that gives $29.38, which is wrong because 13% was applied to the pre-tax amount, not the total.
Common Mistake
Many people multiply the total by 13% to find the tax. This is incorrect. If your receipt says $113.00, the HST is $13.00 (not $14.69). Always divide by 1.13, then subtract. The calculator above does this correctly for you.
Reverse HST Calculator FAQs
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