How to calculate GST
To calculate GST, multiply the price before tax by 0.05; to find the total, multiply by 1.05. The Goods and Services Tax is a 5% federal tax charged on most sales in Canada, and in five provinces it is combined with the provincial tax into one Harmonized Sales Tax (HST).[cra_rates]
Total = price × (1 + combined rate)
Price before tax = total ÷ (1 + combined rate)
Worked example. A $250 purchase in British Columbia carries $12.50 GST and $17.50 PST, $280.00 in total. BC's PST is a separate 7% tax charged on the price before GST, so it is never tax on tax. In Quebec the QST works the same way: 9.975% of the price before GST.[rq_rules]
Remove GST from a total
To remove GST or HST from a total, divide the total by 1 plus the rate, not multiply it by the rate. A $113 receipt in Ontario is $100.00 before tax plus $13.00 HST; taking 13% of $113 would give $14.69, which is wrong. In Alberta, $1,000.00 paid includes $47.62 of GST (1,000 ÷ 1.05 = $952.38). Choose "Total paid" in the calculator to do this for any province; the lines always add back to the cent. To take the tax out of several receipts at once, use the reverse HST calculator.
GST calculator for BC and Alberta
In British Columbia the GST calculator adds two separate taxes, 5% GST and 7% PST, both on the price before tax, so $100 is $112.00 ($5.00 GST + $7.00 PST); in Alberta it adds 5% GST only, so $100 is $105.00.[cra_rates] B.C.'s PST is administered by the province, not the CRA, so a B.C. business claims back only the GST part as an input tax credit. Choose British Columbia or Alberta in the calculator above.
GST rate in Canada by province
The GST rate in Canada is 5% in every province and territory; what changes is the provincial tax added to it. The table compares a $100 purchase.[cra_rates][rq_rates] For all 13 provinces and territories at once, with any amount, use the sales tax calculator for Canada, and for HST provinces, including the federal and provincial split of each HST dollar, use the HST calculator.
| Province | Rate | GST or HST | PST/QST/RST | Total |
|---|---|---|---|---|
| Alberta | 5% | $5.00 | — | $105.00 |
| British Columbia | 12% | $5.00 | $7.00 | $112.00 |
| Saskatchewan | 11% | $5.00 | $6.00 | $111.00 |
| Manitoba | 12% | $5.00 | $7.00 | $112.00 |
| Quebec | 14.975% | $5.00 | $9.98 | $114.98 |
| Ontario | 13% | $13.00 | — | $113.00 |
| Nova Scotia | 14% | $14.00 | — | $114.00 |
| New Brunswick | 15% | $15.00 | — | $115.00 |
| Province or territory | Type | GST/HST | PST/QST/RST | Total |
|---|---|---|---|---|
| Alberta | GST | 5% GST | — | 5% |
| Northwest Territories | GST | 5% GST | — | 5% |
| Nunavut | GST | 5% GST | — | 5% |
| Yukon | GST | 5% GST | — | 5% |
| Saskatchewan | GST + PST | 5% GST | 6% PST | 11% |
| British Columbia | GST + PST | 5% GST | 7% PST | 12% |
| Manitoba | GST + RST | 5% GST | 7% RST | 12% |
| Ontario | HST | 13% HST | — | 13% |
| Nova Scotia | HST | 14% HST | — | 14% |
| Quebec | GST + QST | 5% GST | 9.975% QST | 14.975% |
| New Brunswick | HST | 15% HST | — | 15% |
| Newfoundland and Labrador | HST | 15% HST | — | 15% |
| Prince Edward Island | HST | 15% HST | — | 15% |
Do you have to charge GST? The $30,000 small supplier threshold
You must register for and charge GST/HST once your worldwide taxable sales go over $30,000 in a single calendar quarter or over the last four consecutive calendar quarters; below that you are a "small supplier" and registering is optional.[cra_register] Public service bodies such as charities use $50,000. Taxi and commercial ride-share drivers must register from their first fare whatever their sales.[cra_rc4022]
Small supplier test
$30,000 ruleEnter taxable sales for the last four calendar quarters, oldest first.
Small supplier test
- Four-quarter total
- $34,000.00
- Threshold crossed in
- quarter 4
ResultMust register
Your total passed $30,000 over these four quarters (but not in one quarter). You stop being a small supplier at the end of the month after quarter 4; charge GST/HST from your first sale after that.
Count sales of associated businesses too. Financial services, sales of capital property and goodwill are left out of the total.
The two triggers have different start dates. If one quarter alone goes over $30,000, you stop being a small supplier on the sale that crosses the line and charge GST/HST on that sale; register within 29 days. If you cross the line only over four quarters, small supplier status ends at the end of the month after that quarter, and tax starts on your next sale.[cra_register] Registering voluntarily lets you claim input tax credits for the GST/HST you pay on business costs, but you must stay registered for at least a year.
What a GST/HST receipt must show
To claim the GST/HST it paid as an input tax credit, a business needs a receipt or invoice whose required details depend on its total: under $100, from $100 to $499.99, and $500 or more.[itc_regs] These thresholds replaced the old $30 and $150 limits in 2021, and each calculator result on this site states the rule for its own total. Without the supplier's GST/HST number on a receipt of $100 or more, the CRA can deny the credit.
| Receipt total (including tax) | Must show |
|---|---|
| Under $100 | the supplier's name, the date and the total |
| $100 to $499.99 | the supplier's name, the date, the total, the supplier's GST/HST number and the tax charged (or a note that the total includes it) |
| $500 or more | everything required from $100, plus your name, the payment terms and a description of what was bought |
Charging customers? Check whether you have to register first with the small supplier test above, and see the HST calculator for HST receipts and Ontario's 5% point-of-sale rebate items.
Common GST mistakes
- Removing tax by subtracting the rate from the total (113 − 13%) instead of dividing by 1.13.
- Charging QST or BC PST on top of GST. Both are calculated on the price before GST.
- Using 15% for Nova Scotia. The HST there has been 14% since April 1, 2025.[cra_rates]
- Using your own province's rate for a sale shipped to another province: the place-of-supply rules usually tax a delivered good at the buyer's rate.
- Forgetting the GST/HST credit, now the Canada Groceries and Essentials Benefit with its own payment dates, is a benefit for households, not a refund of tax paid by a business.
More Canadian tax and pay calculators
Each tool below answers one question with dated official figures and a worked example.
- HST calculator: Ontario 13%, Nova Scotia 14%, New Brunswick, Newfoundland and Labrador and PEI 15%.
- Reverse HST calculator: take GST, HST, PST or QST out of up to five receipt totals at once.
- GST/HST explained: which rate to charge across provinces, zero-rated and exempt sales, your GST number and filing deadlines.
- Sales tax calculator Canada: one amount, all 13 provinces and territories side by side.
- GST payment dates: 2026 dates and a calculator for the Canada Groceries and Essentials Benefit.
- Minimum wage Ontario, minimum wage BC, minimum wage Alberta, minimum wage Manitoba, minimum wage Nova Scotia and minimum wage Quebec: current rates with every province compared.
- Vacation pay calculator Ontario, overtime calculator Ontario and severance pay Ontario: Employment Standards Act minimums.
- Property tax Toronto: 2026 City of Toronto rates by property class.
Frequently asked questions
How do I calculate 5% GST?
Multiply the price by 0.05 for the GST, or by 1.05 for the total. $80 × 0.05 = $4 GST, $84 total.
How do I calculate GST backwards from a total?
Divide the total by 1.05 (or 1.13, 1.14, 1.15 for HST) to get the price before tax; the difference is the tax. $105 ÷ 1.05 = $100, so the GST is $5.
How much is GST in BC and Alberta?
Alberta: 5% GST only, $100 → $105. British Columbia: 5% GST plus 7% PST, $100 → $112.
What is the GST rate in Canada in 2026?
5%. The combined sales tax runs from 5% (Alberta and the territories) to 15% (New Brunswick, Newfoundland and Labrador, PEI).
What is the small supplier threshold for GST?
$30,000 of worldwide taxable sales in one calendar quarter or over four consecutive quarters ($50,000 for public service bodies). Above it you must register.
Is QST charged on GST?
No. Since January 1, 2013 Quebec charges 9.975% QST on the price before GST, so $100 costs $5.00 GST + $9.98 QST = $114.98.
Sources
- GST/HST calculator (and rates): GST/HST and PST rates by province; GST/HST rates since April 1, 2013
- When to register for and start charging the GST/HST (small supplier limit, $30,000)
- RC4022, General Information for GST/HST Registrants
- Tables of GST and QST Rates (QST 9.975% since January 1, 2013)
- Basic Rules for Applying the GST/HST and QST (QST is calculated on the selling price excluding GST)
- Input Tax Credit Information (GST/HST) Regulations, SOR/91-45, section 3 (information required under $100, $100 to $499.99 and $500 or more)