For a standard taxable sale in Quebec, the calculation uses 5.00% GST plus 9.97500% QST. Enter the price, then choose Add tax or Remove tax. The province is fixed to Quebec; amounts are in Canadian dollars. The CRA charging guide explains why the type and place of supply must be established before applying a rate.
Calculate a price or receipt
Amount before tax$100.00
GST 5%$5.00
QST 9.975%$9.98
Total with tax$114.98
Example for a standard-rated sale in Quebec. Only explicitly selected provincial taxes are included. JavaScript is needed to change the amount or tax applicability.
To add tax, enter the price before tax. To remove tax, enter the total that already includes the selected taxes. If you change a provincial-tax switch, use the rate that actually applied to the purchase. The result estimates tax arithmetic; it does not determine an exemption, a registration obligation, or eligibility for an input tax credit.
Add tax: the formula
- GST = price before tax × 0.05
- QST = price before tax × 0.09975
- Total = price before tax + the applicable tax amounts.
For a $100 purchase, GST is $5.00, QST is $9.98, and the total is $114.98.
| Price before tax | GST | QST | Total |
|---|---|---|---|
| $20.00 | $1.00 | $2.00 | $23.00 |
| $100.00 | $5.00 | $9.98 | $114.98 |
| $500.00 | $25.00 | $49.88 | $574.88 |
| $1,000.00 | $50.00 | $99.75 | $1,149.75 |
| $2,500.00 | $125.00 | $249.38 | $2,874.38 |
Remove tax from a total
If all the selected standard taxes were included, divide the total by 1.14975 to estimate the price before tax. Multiply that unrounded base by each applicable rate to find the tax components. Do not subtract 14.97500% directly from the total: that percentage was originally applied to a smaller, pre-tax amount.
For a receipt showing $1,149.75, the unrounded base is $1,000.00. GST is $50.00, QST is $99.75. Compare the result with the supplier’s actual invoice. Separately rounded lines or tax components can cause a one-cent difference when reversing a rounded total.
What this province setting does
Calculate QST on the price before GST. Applying 9.975% to a GST-inclusive amount overstates the current standard tax. The QST switch starts on for the combined example. GST and QST can have different treatment for an item; an automatic combined calculation does not decide its classification.
Check the transaction before using the result
A seller’s head-office address does not by itself determine GST/HST. Delivery, the customer address associated with a service, the nature of the supply, and special rules can matter. Start with CRA’s place-of-supply guidance. A zero-rated or exempt supply does not use the standard rate in the examples above.
This is a sales-tax calculator, not an income-tax calculator or a GST/HST return. For business registration, see the GST/HST registration guide. For filing, use the return workflow.
Are QST and GST the same?
No. GST is the federal goods and services tax; QST is Quebec’s provincial sales tax. The standard rates are 5% and 9.975%, applied to the same pre-tax base. They remain separate taxes even when one calculator displays both.
Revenu Québec’s calculation rules confirm the 5% GST and 9.975% QST calculation and cent-rounding rules.