How to Verify a QST Registration Number in Quebec

A QST registration number is the number Revenu Quebec gives a business registered for the Quebec Sales Tax. Before you claim an input tax refund on a Quebec purchase, you need to know the supplier's number is real and belongs to the business on the invoice. This guide covers format-checking and decoding only: what the number looks like, how to read its parts, how to tell it apart from the numbers it gets confused with, and how to run Revenu Quebec's own validation tool. It does not verify any number itself, and it gives no tax advice — if a claim matters, check with your accountant. The check matters because input tax refunds must be supported by invoices showing valid supplier tax registration numbers.

Step 1: Find the number on the invoice

Start with the supplier's invoice. A registered supplier should show its QST registration number on the invoice, alongside its business name. Copy the number exactly as printed, including every digit and the letters TQ. Do not guess at a smudged or cut-off character: if any part is unclear, ask the supplier for the full number before checking it, because a check run on a misread number tells you nothing.

Step 2: Format-check the number

A QST registration number has 16 characters: ten digits, followed by the letters TQ, and four more digits. For example, 1234567890TQ0001. Count the characters first. If the number is shorter, longer, or missing the TQ, stop — it is either not a QST registration number or it was copied wrong. Revenu Quebec's validation tool processes the first ten digits first, and tells you if it needs the remaining characters, so entering only the first ten digits is a valid first attempt, not an error.

Step 3: Decode the parts

The number has three parts, and each part tells you something:

• The first ten digits identify the business in Revenu Quebec's system.
• The letters TQ mark the number as a QST registration number.
• The last four digits are the reference number for that registration.

Knowing the structure helps you spot the common mix-ups in Step 4. A GST/HST account number looks similar but is different: it is 15 characters, nine digits, the letters RT, and four digits, for example 123456789RT0001. Do not enter a GST/HST number into the QST tool, and do not enter a QST number into the CRA's GST/HST Registry — the two systems are separate, and each registry only covers its own tax.

Step 4: Rule out the look-alikes

Two other Quebec numbers get mistaken for QST registration numbers. First, the Quebec enterprise number (NEQ), assigned to a business by the Registraire des entreprises. Revenu Quebec's tool page warns that if the number you are validating starts with 11, 22 or 33, it may be the NEQ, not a QST registration number. The NEQ proves the business is in the enterprise register; it says nothing about QST registration. Second, the nine-digit QST number of a selected listed financial institution. The CRA administers the QST for these businesses on behalf of Revenu Quebec, so neither Revenu Quebec's online service nor the CRA's registry can validate a nine-digit number. Revenu Quebec's tool page directs you to call the CRA at 1-800-959-7775 for those.

Step 5: Run Revenu Quebec's validation tool

Use Revenu Quebec's Validate a QST Registration Number service — the tool's current address, confirmed live at build time. Enter the registration number and submit it. The service returns the number's registration status and the business name it is registered to. Compare that business name with the name on the invoice, in the same order as it is written: the check only supports your input tax refund claim if the number, the name, and the transaction all line up.

The service also validates the QST registration number of a supplier outside Quebec. Effective January 1, 2019, certain suppliers outside Quebec must register for the QST and collect the tax on certain taxable supplies they make in Quebec. If the supplier is outside Quebec and its number begins with NR, note that a business cannot claim input tax refunds on purchases from that supplier, even if the property or service was acquired in the course of its commercial activities.

Step 6: Check the GST/HST side separately

A Quebec supplier usually charges both GST/HST and QST, and the QST check says nothing about the GST/HST number. To check whether a GST/HST registration number is valid, use the CRA's GST/HST Registry. That registry needs three things: the first nine digits of the GST/HST account number only, the supplier's business name, and the transaction date from the invoice. It tells you whether the business was registered on that date, which matters because a supplier can be registered today and not have been registered when it issued your invoice. If you cannot confirm a number after speaking with the supplier, call the CRA's Business Enquiries line at 1-800-959-5525.

Step 7: Save the result with the invoice

Keep a copy of the validation result — a screenshot or a saved page — alongside the invoice it relates to. The record shows you checked the number, the name, and the date, which is what an input tax refund claim rests on. If the tool returns a revoked or cancelled status, or no match at all, do not claim the input tax refund on that purchase until the supplier gives you a number that validates. If the number validates but the name does not match the invoice, ask the supplier to correct the invoice or confirm the correct legal or operating name, and re-check before claiming.

What this guide could not verify

This guide states no QST rate and no registration threshold, because those figures were not needed for a format-check and decode guide and were not verified against Revenu Quebec's pages at build time. It states no check-digit rule for QST numbers, because Revenu Quebec does not publish one. It does not state what the tool returns beyond registration status and business name, because the tool's result screen was not exercised with a live number at build time — no real supplier number was entered, and none should be entered into any tool except Revenu Quebec's own service. The human-readable Revenu Quebec page for this service that some third-party guides link to returned an error at build time, so this guide links only to the working validation tool address confirmed live. Confirm the current rate, threshold, and tool address with Revenu Quebec before relying on them.

Related guides:

• Do You Need a GST Number as a Sole Proprietor in Canada? — when a business must register for GST/HST and what the number is for.
• How to Register a Business in Quebec: the REQ, Your NEQ, and the French-Language Rules — the Quebec enterprise register and the NEQ this guide tells apart from a QST number.
• How to Get a Business Number in Canada: the CRA BN Explained — the nine-digit business number behind the GST/HST account number.
• GST/HST Penalties and Interest in Canada — what happens when GST/HST filings or payments go wrong.

Sources

• Revenu Quebec, Validate a QST Registration Number — the validation service itself, confirmed live at build time; validation of suppliers outside Quebec, the January 1, 2019 rule, nine-digit numbers for selected listed financial institutions and the CRA phone number, the NEQ warning for numbers starting with 11, 22 or 33, and the NR-number input tax refund restriction.
• Canada Revenue Agency, Confirming a GST/HST account number — the CRA's GST/HST Registry for checking a supplier's GST/HST registration, using the first nine digits, the business name, and the transaction date.