GST/HST rulings: free, binding, 45 business days once complete

Ruling, interpretation or phone call: which one binds the CRA?

Only a written ruling binds the CRA. A ruling is the CRA's position on how the law applies to a clearly defined fact situation, and the CRA says it considers itself bound by the rulings it issues. An interpretation covers a generic fact situation (it can even address legislation not yet enacted), and the CRA says plainly it isn't bound by those canada.ca.

The CRA won't issue a ruling on a hypothetical situation or on too few facts; it may answer with an interpretation instead canada.ca. Both written services are free, while advance income tax rulings carry cost recovery fees canada.ca. The income tax process is covered in advance income tax rulings.

The governing document is GST/HST Memorandum 1-4, now titled "Requesting a GST/HST Ruling or Interpretation". The March 2026 version replaced the May 2021 one and moved excise duty, excise tax and the other specialty taxes to a separate service canada.ca.

What does a complete ruling request need?

Paragraph 17 of the memo lists what a ruling request should contain canada.ca:

• Your client's name, phone number, mailing address and business number
• A written authorization if you're acting for the client
• A statement of whether the issue is already being considered by the CRA, under audit, under a notice of objection or before the courts
• A complete description of the facts of each transaction, its purpose and any significant related transactions
• Your interpretation of the provisions, any common law or Civil Code of Québec issue, and the exact interpretive concern
• Copies of the agreements, with a summary of the relevant clauses
• Your analysis of the authorities for and against your position

The authorization trips up firms. It has to be specific to the ruling request: name you and your firm, the tax (GST/HST, for example) and the period it covers. A Form AUT-01 offline access authorization doesn't count for this purpose canada.ca.

If the transaction raises anti avoidance, add a submission that it doesn't misuse or abuse the legislation canada.ca. The GST/HST avoidance rule sits in section 274 of the Excise Tax Act laws-lois.justice.gc.ca. For a food product, the request must also meet the information requirements in Notice 338 for basic grocery rulings canada.ca.

Where do you send the request, and who handles Quebec?

Send it online through the Submit documents service once you've signed in to a CRA account; individuals, businesses and registered representatives can all use it canada.ca. The sign in page covers My Account, My Business Account and Represent a Client canada.ca.

By mail, the address is GST/HST Rulings Directorate, Canada Revenue Agency, Place de Ville Tower A, 5th floor, 320 Queen St, Ottawa ON K1A 0L5. Faxes go to 418-556-1846, but the CRA doesn't guarantee fax confidentiality and won't reply by fax canada.ca.

A business located in Quebec asks Revenu Québec instead (1-800-567-4692), because Revenu Québec generally administers the GST/HST there. The exception is a selected listed financial institution: the CRA administers both GST/HST and QST for those wherever they are, with technical enquiries at 1-855-666-5166 canada.ca.

Expect an acknowledgement letter with a case number, then, once work on the file begins, contact from an officer to clarify facts or ask for more information. Requests are generally handled in the order received, and a request with several issues may come back as separate letters canada.ca.

When does the 45 business day clock start?

The clock starts only once the CRA has the request and all relevant facts and supporting documents. Highly technical, precedent setting and policy setting files are excluded, and the CRA aims to hit the target 80% of the time, so it's a goal rather than a deadline canada.ca.

Worked example: your request reaches the Directorate on Tuesday, September 1, 2026, without the lease it relies on. The officer asks for it, and it arrives on Monday, September 14. Counting from the next business day and skipping the CRA holidays (Labour Day, September 30, Thanksgiving and Remembrance Day) canada.ca:

The missing lease cost 8 business days before anyone read the file. Attach every agreement the first time and summarize the clauses you rely on.

When can a ruling stop protecting your client?

A ruling is only as good as the facts behind it. It covers only the person it was requested for, only the facts and issues it addresses, and it may carry conditions such as a time limit. The CRA stops being bound from the effective date of a change in the law, its interpretation of the law or its administrative policy, and it expects you to watch for those changes canada.ca.

The CRA can also revoke or amend a ruling it decides is wrong. If the CRA made the error, the change generally takes effect from the date of its letter (you can ask for an earlier date). If your client gave incomplete or inaccurate facts, the change reaches back to the date of the original ruling canada.ca.

The facts behind a ruling can still be checked on audit. And the CRA may decline to rule at all when the same issue is in dispute or under assessment, a notice of objection is being considered, the matter is before the courts, or the request involves draft legislation, a fair market value or a tax calculation canada.ca. If the real goal is to correct past filings, look at amending the GST/HST return or the Voluntary Disclosures Program instead.