GST and QST (Quebec Sales Taxes)
GST and QST are the sales taxes Quebec contractors collect and remit on taxable work. Learn registration, invoicing, and common mistakes for English speakers in Quebec.
Quick definition
GST and QST (Quebec Sales Taxes) means GST and QST are the sales taxes Quebec contractors collect and remit on taxable work. Learn registration, invoicing, and common mistakes for English speakers in Quebec.
What are GST and QST?
In Quebec, most taxable business sales include two sales taxes:
- GST (Goods and Services Tax): the 5% federal tax administered by the Canada Revenue Agency (CRA)
- QST (Quebec Sales Tax): the 9.975% provincial tax administered by Revenu Québec
French paperwork and government sites often use TPS (taxe sur les produits et services) and TVQ (taxe de vente du Québec). Same taxes, different language. English invoices and accounting software typically show GST and QST.
If you are registered, you collect both taxes on taxable supplies, show them separately on invoices, and remit them to the respective agencies on schedule.
Who must register?
Registration rules depend on revenue thresholds and business type. In general:
- GST registration is required once taxable revenue exceeds the federal small-supplier threshold (currently $30,000 over four consecutive quarters for most businesses)
- QST registration follows Quebec rules, which often align closely but are not identical in every detail
Many growing contractors hit the threshold mid-year and register late. That creates back-tax, interest, and messy invoice corrections. Track rolling revenue monthly once you are close.
Voluntary registration before the threshold is sometimes worth it so you can claim input tax credits on business purchases (tools, materials, vehicle expenses, software, and more). Ask your accountant whether early registration makes sense for your numbers.
What to show on a Quebec contractor invoice
When you are registered, a professional invoice should include:
| Element | Why it matters |
|---|---|
| Business name and address | Identifies the supplier |
| NEQ (Quebec enterprise number) | Standard business ID in Quebec |
| GST and QST registration numbers | Required on tax invoices |
| RBQ licence number | Not a tax rule, but clients often expect it on construction invoices |
| Invoice number and date | Audit trail and payment tracking |
| Description of work | Supports the amount if disputed |
| Subtotal before tax | Base for tax calculation |
| GST amount (5%) | Shown separately |
| QST amount (9.975%) | Shown separately |
| Total due | What the client pays |
If you are not registered (under the threshold and not voluntarily registered), do not charge GST or QST. Still issue a clear invoice for your records and for the client.
How remittance works
Registered businesses file returns and remit taxes collected minus eligible credits on purchases used in the business.
- GST returns go to the CRA
- QST returns go to Revenu Québec
Filing frequency (monthly, quarterly, or annual) depends on revenue and registration details. Set aside tax collected in a separate account so you are not spending Revenu Québec's money.
GST/QST on construction work
Most construction and renovation services in Quebec are taxable supplies. Common questions:
Deposits and progress billings: tax applies when you invoice, not when cash hits your account. Match your invoice timing to your tax reporting.
Materials vs labour: on a typical contractor invoice, both are usually part of the taxable supply to the client. Do not invent separate tax treatment without professional advice.
Residential renovations: some specific rules and rebates exist in Quebec (for example, certain renovation tax credits for homeowners). Those programs affect the homeowner, not your obligation to charge tax on a taxable service.
Out-of-province clients: place-of-supply rules can get complex. If you work outside Quebec or for clients in other provinces, confirm treatment before quoting.
Common mistakes
Charging tax without being registered. Clients may pay it, but you still owe remittance and face penalties.
Not charging tax after registration. You absorb 14.975% out of pocket on every job until you fix your invoices.
One "tax-in" line with no breakdown. Revenu Québec expects GST and QST shown separately on registered invoices.
Mixing personal and business purchases. Input tax credits apply only to legitimate business expenses with proper documentation.
No invoice at all. Cash and e-transfer jobs still need records. Invoices support tax filings and payment disputes.
Record keeping
Keep invoices, receipts, bank records, and tax filings for at least six years. That matches typical CRA and Revenu Québec audit windows.
Good invoicing software helps, but the underlying rule is simple: document what you charged, what tax you collected, and what you paid on business inputs.
Disclaimer
This glossary entry is general information only, not tax advice. Registration thresholds, filing deadlines, and place-of-supply rules change. Consult an accountant familiar with Quebec construction businesses, Revenu Québec, and the CRA for your situation.
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