Quebec GST + QST Calculator

How to calculate Quebec's 14.975% GST + QST

Both taxes are calculated on the same pre-tax price and added together. Adding tax: GST = price × 0.05, QST = price × 0.09975, total = price × 1.14975. Removing tax from a total: price = total ÷ 1.14975, then split that price back into its 5% and 9.975% pieces.

Worked example on $100

A $100 purchase: GST = $100 × 0.05 = $5.00. QST = $100 × 0.09975 = $9.98 (rounded). Total = $100 + $5.00 + $9.98 = $114.98. Working backwards from that $114.98 total: price = $114.98 ÷ 1.14975 ≈ $100.00, combined tax ≈ $14.98.

What's taxed and what's QST-exempt

QST generally follows the same base as GST, so most exemptions line up: basic groceries, prescription drugs, most health and dental services, and long-term residential rent are exempt from both taxes. A $6 coffee-shop sandwich to go is taxed at the full 14.975%, while raw grocery ingredients for the same sandwich are tax-free. Books are a Quebec-specific case: printed books are QST-exempt but still carry the 5% GST. Most services (haircuts, legal fees, repairs) are fully taxable at 14.975% unless specifically exempted.

Why Revenu Québec, not the CRA, handles GST here

Under an agreement between Quebec and the federal government, Revenu Québec administers the federal GST inside Quebec's borders in addition to its own QST. That means a Quebec business dealing with GST registration, returns, audits or objections generally deals with Revenu Québec directly rather than the CRA — the only province where the provincial revenue agency is the main point of contact for both taxes.

QST used to be a tax on a tax

Before 2013, Quebec calculated QST on the GST-inclusive price — tax charged on top of tax — which pushed the effective combined rate slightly above the sum of the two rates. Quebec changed this on January 1, 2013, so QST is now calculated on the same pre-tax amount as GST, and raised the QST rate from 9.5% to 9.975% to keep total revenue roughly the same. The 14.975% this calculator applies reflects that current, non-compounding method.

Registering to collect GST and QST as a small business

Businesses register both taxes at once, directly with Revenu Québec, using the "Register a Business" service (form LM-1-V) — there's no separate CRA step for GST inside Quebec. Registration is mandatory once total taxable revenue (including associated businesses) passes $30,000 over four consecutive calendar quarters or within a single quarter; below that you're a small supplier and registration is optional. Once registered, you charge 5% GST and 9.975% QST on taxable sales, file returns on your assigned schedule, and remit what you collect (minus input tax refunds) to Revenu Québec.

Quebec at a glance

Official sources

• Canada Revenue Agency — GST/HST rates by province
• Revenu Québec — GST/HST and QST

Both sources checked 30 September 2026.

Frequently asked questions

Why is Quebec's combined rate 14.975% instead of a round number?

It's simply 5% GST + 9.975% QST added together on the same pre-tax base — the QST rate itself was set at 9.975% in the 2013 delinking reform.

Do I deal with the CRA or Revenu Québec for GST in Quebec?

Revenu Québec. It's the only provincial agency that administers the federal GST on the CRA's behalf, alongside its own QST.

Are books taxed in Quebec?

Printed books are QST-exempt but still carry the 5% GST, so they're taxed lower than most goods but not tax-free.

Is QST calculated on the price including GST?

No, not since 1 January 2013. QST is calculated on the same pre-tax price as GST, so the two don't compound.