QST calculator
Add or remove Quebec’s 9.975% QST, charged alongside the 5% federal GST.
Calculation mode
- Subtotal
- $100.00
- GST 5%
- $5.00
- QST 9.975%
- $9.98
- Total
Get it on your phone
The same calculator, offline, with every province built in.
How it’s calculated
Adding tax to $100.00
Total = price × (1 + combined rate)
- Subtotal
- $100.00
- GST 5%
- $5.00
- QST 9.975%
- $9.98
- Total
- $114.98
Removing tax from $100.00
Price = total ÷ (1 + combined rate)
- Subtotal
- $86.98
- GST 5%
- $4.35
- QST 9.975%
- $8.67
- Total
- $100.00
Examples use Quebec at 14.975%. Change the province above to see another.
Quebec’s own value-added tax
The QST is Quebec’s provincial sales tax, charged alongside the federal GST. Unlike PST and RST out west, it’s a value-added tax, so registered businesses recover it through input tax refunds much as they recover GST through input tax credits.
Revenu Québec administers both the QST and the federal GST within Quebec, under an agreement with the federal government. That’s unique in Canada.
The compounding myth
Revenu Québec is explicit: the QST is calculated on the selling price excluding the GST. The two taxes apply to the same base, side by side. You’ll still find calculators online that apply the QST to the GST-included amount, which produces a total a few cents too high on every line.
One step or two
If your register calculates the taxes in two steps, apply the 9.975% QST rate to the sale price. If it calculates them in one step, use the 14.975% combined rate. Both give the same answer, because nothing compounds. The rounded rates 9.97% and 14.97% are permitted only where a register cannot process three decimals — and Revenu Québec requires that 9.97%, 14.97% and 14.975% never appear on the document attesting to the sale.
See the Quebec page for invoicing details and worked examples.
Common questions
Is QST calculated on the GST-included price?
No. Revenu Québec calculates QST at 9.975% on the selling price excluding GST. Both taxes apply to the same base.
Why do some calculators give a different total?
Because they compound the QST on top of the GST. That was how it worked before January 1, 2013, and some tools never updated. The result is a few cents too high on a $100 sale.
Can I use a single combined rate?
Yes. Revenu Québec requires the 14.975% rate when a register calculates both taxes in one step. It gives the same answer.
Who administers the QST?
Revenu Québec, which also administers the federal GST within Quebec under an agreement with the federal government.
Do I need a separate QST registration?
Quebec businesses generally deal with Revenu Québec for both taxes. Sellers outside Quebec may have separate obligations, including under the specified-supplier regime for digital products.