How to verify a supplier’s GST/HST number in Canada

Start with the invoice, not a general business search

Keep the original receipt, invoice, contract, or other business paper in front of you. Record the supplier name exactly as shown, the tax account number, and the transaction date before opening a registry. Those facts let you test the document the supplier actually issued rather than a similar business found through a general web search.

A corporate registration, a nine-digit business number, and a GST/HST program account are related but not interchangeable. CRA describes a program account as the nine-digit business number followed by a two-letter program identifier and a four-digit reference number. GST/HST uses RT. The appearance of that format alone does not confirm registration status.

Québec identifiers need the same care. An ordinary QST number uses ten digits, TQ, and four more digits. Do not substitute a Québec enterprise number, a federal business number, or another tax identifier for the number printed on the supplier’s business paper.

Use the CRA registry with three matching facts

CRA’s GST/HST Registry is free. It asks for only the first nine digits of the GST/HST account number, without the letters, plus the supplier’s legal, operating, or trading name and the transaction date. The transaction date is the date on the receipt, invoice, contract, or other business paper.

Use the supplier name from the document, including the legal or operating form when shown. If the registry returns no result, CRA says to contact the business owner for the exact name supplied to CRA. A spelling, punctuation, trade-name, or date mismatch should be resolved rather than repeatedly changed until something happens to match.

CRA says a supplier must include its GST/HST account number on receipts, invoices, contracts, or other business papers for taxable supplies of C$100 or more. If the number is missing, request it from the supplier and use CRA’s current contact route when the supplier does not provide it.

• Enter the first nine digits—not RT and not the four-digit reference suffix.
• Match the supplier name to the invoice or other business paper.
• Use the transaction date from that same document.
• Treat no result as a discrepancy to resolve, not as permission to invent a different number or date.

Use Revenu Québec for an ordinary QST number

Revenu Québec’s QST validation service is the official route for an ordinary QST registration number. Its published service information describes the required format as ten digits followed by TQ and four digits, and says the result can include the status, effective date, business name, and commercial name.

Use those returned facts to compare the account with the supplier and the purchase date. A valid-looking TQ format is only a format check; the official result is the evidence that addresses status. Preserve the number exactly as shown on the supplier document and do not place a real supplier identifier into a search-engine query.

A special QST number containing only nine digits and no TQ can belong to a selected listed financial institution whose QST is administered through CRA. CRA and Revenu Québec state that the ordinary online validators cannot confirm that special path. Follow the current CRA contact instructions instead of forcing the number into an incompatible form.

Save evidence before relying on the tax

After a successful GST/HST check, CRA specifically says to print the Search Details screen. Retain that output with the purchase record so a later reviewer can see the account number checked, supplier name, transaction date, result, and when the check was performed.

For a QST check, preserve the official result, the effective-date information shown, the transaction reference, and the date you performed the check. Keep the invoice and any corrected document with the result. A screenshot without the underlying invoice or a registry result without the transaction date leaves an incomplete trail.

Thirty North’s number checker recognizes common RT and TQ formats in the browser and opens the appropriate official service without placing the identifier in the outgoing link. It does not query either registry, receive the identifier, confirm active registration, or decide whether an input tax credit or input tax refund is available.

Resolve a mismatch before treating the file as complete

Do not edit an invoice number, supplier name, or transaction date merely to produce a match. Ask the supplier to confirm the legal or operating name registered with the agency and to issue a corrected business paper when the original document is incomplete or wrong.

A successful registry match is one control, not the entire input tax credit analysis. Purchaser identity, the nature and commercial use of the supply, tax paid or payable, supporting-information requirements, accounting method, time limits, and other facts can still matter.

Escalate material, repeated, or unresolved discrepancies to CRA, Revenu Québec where applicable, or a qualified adviser before relying on the tax. Keep the unresolved amount visible in the purchase review rather than silently treating it as confirmed.