To register for GST/HST in Canada, go online to the CRA's Business Registration Online (BRO), where you get a nine-digit business number and a GST/HST (RT) program account — usually instantly. You must register once your worldwide taxable revenue passes $30,000 over four consecutive calendar quarters (or in a single quarter), and you have 29 days from the sale that crosses the threshold to do so. This is a focused how-to: how to register, set your effective date, file returns, and claim input tax credits. For rates by province and how the system works conceptually, see our GST/HST/PST overview.
Step 1 — Confirm you have to register
The trigger is the $30,000 small-supplier threshold. As of the 2026 tax year:
- At or under $30,000 in worldwide taxable revenue over four consecutive calendar quarters → you are a small supplier; registration is optional.
- Over $30,000 — in a single calendar quarter, or cumulatively across four consecutive quarters → registration is mandatory.
The test is rolling, not tied to your fiscal year. The sale that pushes you past $30,000 must itself include GST/HST, and you then have 29 days to register. Taxi and ride-share drivers must register from their first fare, regardless of revenue.
Even below $30,000, voluntary registration is often worthwhile — it lets you recover GST/HST on startup costs (see Step 5).
Step 2 — Register online and get your business number
The CRA registers businesses through Business Registration Online (BRO). As of November 2025, the CRA no longer accepts GST/HST registration by phone, so online is the standard route. You will:
- Sign in (or register) and open Business Registration Online.
- Provide your legal name/business name, structure (sole proprietor, partnership, corporation), and contact details.
- If you don't already have one, you'll be issued a nine-digit business number (BN) on the spot.
- Add the GST/HST program account — the BN followed by RT0001 (e.g.,
123456789 RT0001).
You'll also confirm your estimated annual revenue (which sets your default filing frequency), your reporting period, and your effective date.
Step 3 — Set the right effective date
Your effective date of registration is the moment your obligations begin — and your right to claim input tax credits.
- Mandatory registration: the effective date is the day of the sale that put you over $30,000. From that day you must charge GST/HST.
- Voluntary registration: you choose the date. It can generally be backdated up to 30 days, or earlier with supporting records — useful when you've already incurred taxable startup costs you want to recover.
Get this right: too late an effective date and you've collected nothing on taxable sales you were obligated to tax; too early and you take on filing duties before you need them.
Step 4 — Charge, collect and file
Once registered, you charge GST/HST on every taxable sale at the rate for the place of supply (5% in Alberta; 12% combined in BC with PST filed separately; 13% HST in Ontario). You then file a GST/HST return for each reporting period.
Filing frequency is driven by annual taxable sales:
| Annual taxable supplies | Default filing frequency |
|---|---|
| $1.5 million or less | Annual |
| Over $1.5 million up to $6 million | Quarterly |
| Over $6 million | Monthly |
You can elect to file more frequently (e.g., quarterly instead of annual) if you regularly expect refunds. Most registrants file electronically via CRA My Business Account, GST/HST NETFILE, or accounting software. On the return you report:
- Line 105 — total GST/HST collected on sales.
- Line 108 — total input tax credits (ITCs) on purchases.
- Net tax = collected − ITCs → you remit the difference or claim a refund.
You must file even for a nil period. Annual filers whose net tax was $3,000 or more in the prior year may also owe GST/HST instalments.
Step 5 — Claim input tax credits (ITCs)
This is where registration pays off. Input tax credits recover the GST/HST you pay on business purchases — supplies, equipment, rent, professional fees, software. You subtract ITCs from the tax you collected and remit only the net; if you paid more on inputs than you collected (common in a startup buying equipment), you get a refund.
To claim ITCs you need valid supplier documentation: invoices/receipts showing the GST/HST charged and, for larger purchases, the supplier's GST/HST number. After registering you can generally claim ITCs back four years, and in some cases recover tax on inventory and capital property on hand at your effective date — another reason early voluntary registration helps. Note that PST in BC is generally not recoverable this way; only GST/HST flows through as ITCs.
Optional: the Quick Method
The Quick Method simplifies filing for smaller businesses. Instead of tracking every ITC, you remit a flat percentage of your GST/HST-included sales, and you get a 1% credit on the first $30,000 of eligible revenue each year. As of 2026, you can elect the Quick Method if your annual worldwide taxable supplies are $400,000 or less (GST/HST included), and your business isn't in an excluded category — which includes accountants, bookkeepers, lawyers and financial consultants.
The Quick Method usually wins for service businesses with few taxable purchases, because the flat remittance rate is lower than the tax you collect, and you skip detailed ITC tracking. Businesses with large input costs (lots of recoverable GST/HST) are typically better off on the regular method. Model both before electing.
Closing or changing a registration
If you stop carrying on business, or drop back to small-supplier status and want to deregister, you close the RT account through My Business Account — but you must account for GST/HST on any capital property and inventory on hand at deregistration. If your sales grow past a frequency band, your filing frequency changes accordingly.
Model the tax on a sale with our sales tax calculator, and browse common questions in our GST FAQ hub.
How RN Canada helps
RN Canada is an accounting and advisory firm with offices in Edmonton and Vancouver, led by Ozgur Duymaz, Ph.D., CPA (Canada), ACCA (UK), CMA (US). We handle GST/HST registration end to end — choosing the right effective date, running the voluntary-registration analysis for startups, electing the Quick Method where it saves money, and filing accurate returns with full input-tax-credit recovery. We also manage BC PST registration where it applies. See our bookkeeping and tax filing service to get your sales-tax compliance set up correctly from day one.
Frequently asked questions
Register online through the CRA's Business Registration Online (BRO) service. You provide your business details and, if you don't already have one, you receive a nine-digit business number plus a GST/HST program account (the RT account). As of late 2025 the CRA no longer takes GST/HST registrations by phone, so online registration is the standard route and is usually instant.
You must register once your worldwide taxable revenue exceeds $30,000 in a single calendar quarter or over four consecutive quarters. The very sale that pushes you over the threshold must include GST/HST, and you then have 29 days from that date to register. Below $30,000 you are a small supplier and registration is optional, though often worthwhile.
Your effective date of registration is the day of the sale that put you over the $30,000 threshold. From that date you must charge and collect GST/HST and you can claim input tax credits. If you register voluntarily, you choose the effective date (it can be backdated up to 30 days, or earlier with support). Getting the date right matters because it sets when your obligations begin.
Most registrants file electronically through CRA My Business Account, GST/HST NETFILE or their accounting software. You report GST/HST collected on sales (line 105), subtract input tax credits on business purchases (line 108), and remit the net (or claim a refund). Filing frequency — annual, quarterly or monthly — depends on your annual taxable sales, and you must file even for a nil period.
The Quick Method lets eligible small businesses remit a flat percentage of GST/HST-included sales instead of tracking every input tax credit, plus a 1% credit on the first $30,000 of revenue. You still charge tax at the normal rate but remit less. It suits service businesses with few taxable purchases, and is available if annual taxable supplies are $400,000 or less, with some sectors excluded.
Yes, within limits. Once registered, you can claim input tax credits on GST/HST paid on business purchases from your effective date forward, and in some cases on inventory and capital property on hand at registration. Most ITCs can be claimed within four years. This is why voluntary early registration often pays off for businesses with significant startup spending.