GST/HST registration
GST/HST registration is the process of obtaining a sales-tax account so a business can charge GST or HST, claim input tax credits, and file returns with the CRA — or with Revenu Québec if the business operates in Québec.
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Key facts
| Category | GST, QST & HST |
|---|---|
| Also known as | GST number, business number GST account, RT account |
| Mandatory when | You cease to be a small supplier, or make taxable supplies in a category with no threshold |
| Effective date | Fixes when you must start charging and may start claiming |
| Obtained from | The CRA; Revenu Québec for most Québec businesses |
| Part of | The business number, as the RT program account |
| Authority | Canada Revenue Agency; Revenu Québec |
What it means in practice
Registration is mandatory once taxable supplies exceed the small-supplier threshold of $30,000 over four consecutive calendar quarters. The test is rolling rather than calendar-year, and it aggregates the worldwide taxable supplies of the business together with those of its associated companies. Cross the threshold within a single quarter and registration is required immediately, with tax charged from that transaction onward. Cross it across four quarters and there is a one-month grace period before the obligation begins. A GST/HST account is an RT account attached to the business number. Québec businesses generally register with Revenu Québec, which administers both GST and QST for most registrants, rather than dealing with the CRA separately. Registering voluntarily below the threshold is often worthwhile: it converts the sales tax paid on start-up equipment, leasehold work and professional fees into recoverable input tax credits.
The effective date is the decision that matters
Registration is not just paperwork — it fixes the date from which you were required to charge tax and entitled to recover it. Backdating gives access to input tax credits on earlier purchases, but it also creates an obligation to remit tax on sales already invoiced without it. Where a business has been over the threshold for some time, the effective date is usually set to the date the obligation actually began. Tax not charged to those customers is still owed, and it is generally easier to invoice a business customer for a missed amount than to absorb it, since a registered customer simply claims it back. Registering also brings filing obligations that continue whether or not you have sales in a period. A nil return still has to be filed.
FAQ
Can I register before I have any revenue?
Do non-resident businesses selling into Canada have to register?
Need this applied to your situation?
A definition only gets you so far. Talk to a Montréal CPA about what this means for your return — in English or French.