What a Québec invoice must show: GST, QST, both numbers, French — the rules by amount

A Québec invoice answers to two tax authorities at once. The Canada Revenue Agency wants the GST shown and the seller's GST/HST number on the document; Revenu Québec wants the QST shown and the seller's QST number beside it; the Charter of the French language wants the document available in French. None of this is complicated once it is written down, and most of it turns on how much the invoice is for. This page sets the rules out by amount, says what "shown" means in practice, and ends with what KRONENWERK checks before a Québec invoice gets its number — and what it leaves to you and your accountant.

Why the customer cares as much as the tax office

The rules are written from the buyer's side. A business customer recovers the GST it paid as an input tax credit and the QST as an input tax refund, and it may only do so with a document that carries the prescribed information. An invoice that lacks the seller's registration numbers is not illegal for the seller; it is useless for the buyer, whose bookkeeper will phone, hold the payment and ask for a corrected copy. That phone call is the cost of a bad invoice, and it lands on your receivables, not on your tax return. The thresholds below are therefore the buyer's thresholds: the more the invoice is for, the more it has to say.

The three thresholds

The federal regulations set three tiers by the total amount paid or payable on the document. The tiers were $30 and $150 for many years; since 20 April 2021 they are $100 and $500. Revenu Québec applies the same information requirements to the QST, so one document serves both taxes.

Two practical readings. First, the tiers are minimums for the buyer's claim, not a licence to leave things off: a business that always prints both numbers, the customer's name, a description and the payment terms never has to think about which tier an invoice falls in, and its customers never have to ask. Second, "the amount of each tax" is read literally in Québec: the GST and the QST are two taxes with two rates and two numbers, and a document that shows one merged 14.975 % line tells the buyer's bookkeeper the right total and the wrong thing about who was paid. Show them as two lines, each with its own amount.

The numbers, the rates, the words

The GST/HST registration number is the nine-digit business number followed by the program identifier RT and a four-digit reference, in the form 123456789RT0001. The QST registration number is a ten-digit number followed by TQ and a four-digit reference, in the form 1234567890TQ0001. Both belong on every invoice from $100 upward, and it costs nothing to print them on every invoice. The customer can confirm the GST/HST number on the CRA's registry and the QST number on Revenu Québec's; a mismatch between the name on the invoice and the name in the registry is the second most common reason a business customer's payment stalls.

The GST rate is 5 % and the QST rate is 9.975 %, each computed on the price before tax, so the two never compound. Whether a given sale is taxable, zero-rated or exempt is a question of what you sell, to whom and where: a sale delivered to Ontario carries one HST line rather than GST and QST, a sale to a customer in Vermont is usually a zero-rated export, a sale of certain basic groceries is zero-rated everywhere. Those decisions are yours and your accountant's; the invoice records what you decided.

The words matter too. The federal side accepts "GST" or "TPS", the Québec side "QST" or "TVQ"; a French document uses Facture, TPS, TVQ, Sous-total and Montant dû, an English one Invoice, GST, QST. The Charter of the French language requires that invoices, receipts and similar commercial documents be available in French; a bilingual document is permitted as long as the French text is treated no less favourably than the other language. For a Montréal business selling to a bilingual clientele, the simplest policy is one document language per customer, chosen on the customer record.

Registration, small suppliers and the first invoice

A business must register for the GST/HST and the QST once its worldwide taxable sales exceed $30,000 over four consecutive calendar quarters; below that it is a small supplier and may not charge either tax unless it registers voluntarily. The moment you register, the numbers must appear on your invoices from $100 upward, and the moment you charge a tax you must be registered for it: charging QST without a QST number is the one thing a piece of software can and should refuse outright.

Record keeping runs the same for both authorities: keep the invoices you issue and the ones you receive, together with the books that rest on them, for six years after the end of the year they relate to. An invoice that was corrected is corrected with a credit note and a new document, not by editing the old one; the sequence of numbers must remain unbroken so that an auditor can see that nothing was removed.

What KRONENWERK checks before a Québec invoice gets a number

• Two tax lines, two numbers. GST and QST are entered as two taxes on the line — in the web form, through the API and through the AI assistant — and printed as two lines, each computed on the net, each with its rate and amount, with both registration numbers on the document.
• No QST without a QST number. A company that tries to charge QST with no QST registration on file gets a refusal with the reason, before any number is spent.
• The customer's province decides the structure. The province is on the customer record; an invoice for an Ontario customer carries one HST line, one for a British Columbia customer GST and, where you say so, PST as the second tax, and KRONENWERK warns when the document does not carry the structure the province suggests.
• French or English, from one source. The document language is a choice on the customer, and it changes nothing about the company's country or its taxes.
• Frozen once issued. An issued invoice is kept as a snapshot with its PDF; corrections are credit notes; the numbering has no gaps.

What it does not do: it does not determine the rate or decide whether a supply is taxable, zero-rated or exempt; it does not file the GST/HST or QST return — the figures per rate are in the reports, the filing is on the CRA's and Revenu Québec's portals; and it does not give tax advice. The Montréal page sets the same limits out in full.

How KRONENWERK handles this

SUPPORTED WITH LIMITATIONS Québec invoices with GST and QST on separate lines and both registration numbers, checked before issue; refusal of QST without a QST number; province-aware structure warnings; Canadian French and English documents; frozen documents and gap-free numbering; six-year retention of documents and attachments. Not done: rate determination, taxable/zero-rated/exempt decisions, filing, tax advice. See the Canada page and invoices; for sales across the border, invoicing a US customer from Canada.