Written by Maryam Ajorloo, CPA · Reviewed by Behdad Karimi Dermeni, CPA
Somewhere between landing your first big client and losing an evening to paperwork, most Canadian business owners run into the same question: do I need to register for GST/HST, and how do I actually do it? The good news is that GST registration is one of the more straightforward things the Canada Revenue Agency (CRA) asks of you. This guide walks through when you have to register, how to get your GST number, and what happens the day after.
How do you register for GST/HST in Canada? You get a business number (BN) from the CRA, then open a GST/HST program account, usually online through Business Registration Online. Registration becomes mandatory once your taxable revenue passes $30,000 over four consecutive calendar quarters (or in a single quarter), and it is completely free.
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The Rule of Thumb for GST Registration
Here is the one rule that explains most of this: once your business earns more than $30,000 in taxable sales over four consecutive calendar quarters, GST/HST registration stops being optional. Below that line, you are what the CRA calls a small supplier, and registering is your choice.
Notice the word "sales," not "profit." The $30,000 threshold is measured on your revenue from taxable supplies, not the money left over after expenses. (The CRA is not especially interested in how much of your revenue went to a very necessary new laptop.) Get that distinction right and the rest of GST registration is mostly logistics.
What GST, HST, PST, and QST Actually Mean
Sales tax in Canada goes by a few names depending on where you do business, which is half the confusion. Here is the short version:
GST is the 5% federal Goods and Services Tax that applies across the country.
HST is the Harmonized Sales Tax, which bundles the federal GST together with a provincial portion into one combined rate.
PST is a separate Provincial Sales Tax that some provinces charge on top of GST, and in Quebec the provincial equivalent is called QST.
When you register federally, you register for GST/HST in one step. Whether you collect plain GST or the harmonized HST depends on the province where your sale takes place, not where your business is based.
GST vs. HST vs. PST by Province (2026)
HST provinces (one combined rate):
Ontario: 13%
New Brunswick: 15%
Newfoundland and Labrador: 15%
Prince Edward Island: 15%
Nova Scotia: 14% (reduced from 15% on April 1, 2025)
GST plus a separate provincial tax:
British Columbia: 5% GST + 7% PST
Saskatchewan: 5% GST + 6% PST
Manitoba: 5% GST + 7% PST (RST)
Quebec: 5% GST + 9.975% QST
GST only (5%, no provincial sales tax):
Alberta, plus Yukon, the Northwest Territories, and Nunavut
For a fuller breakdown of how these overlap, see our guide on the difference between GST and HST.
When Do You Have to Register for GST/HST?
The $30,000 small supplier threshold has two triggers, and they work on different timelines. This is the part most guides gloss over, so it is worth slowing down for.
The four-quarter test: If your total taxable revenue exceeds $30,000 over the previous four consecutive calendar quarters, you stop being a small supplier. You then have to register, and your effective date of registration is the day of the supply that pushed you past the limit going forward.
The single-quarter test: If one big sale pushes you over $30,000 within a single calendar quarter, you cease to be a small supplier immediately. You have to charge GST/HST on that very sale, even though you are not registered yet, and register right away.
Either way, you have 29 days from your effective date of registration to actually register with the CRA. Miss that window and you still owe the tax you should have collected, so it pays to watch your rolling revenue rather than waiting for a year-end surprise.
There are also a couple of situations where the $30,000 threshold does not apply at all. Taxi and ride-share drivers must register for GST/HST from their very first fare, regardless of income. Non-resident businesses selling taxable goods or services in Canada may also have to register. When in doubt, a quick check with a CPA beats a guess.
Should You Register Voluntarily Before $30,000?
You are allowed to register before you hit the threshold, and for a lot of businesses it is a smart move. Voluntary GST registration lets you claim input tax credits (ITCs), which recover the GST/HST you pay on business expenses like equipment, software, and supplies.
The math is simple: if you are spending money to get the business going, registering early means you can claim back the sales tax on those purchases instead of eating it. The trade-off is that you now have to charge tax to your customers and file returns, so it makes the most sense once you are buying real inputs or you can see the $30,000 line coming.
How to Register for GST/HST in Canada: Step-by-Step
Registering for a GST number takes most people about 15 to 20 minutes, and there is no fee. Here is the process from start to finish.
Step 1: Confirm You Actually Need to Register
Before anything else, check your rolling revenue against the $30,000 threshold using the two tests above, and decide whether voluntary registration makes sense for you. If you are registering by choice, pick an effective date that lets you start claiming ITCs on the expenses you care about.
Step 2: Get or Locate Your Business Number (BN)
Your business number is the 9-digit identifier the CRA uses for your business. A corporation usually already has one from when it was incorporated. If you are a sole proprietor or partnership without a BN yet, you do not need to get it separately first, you will receive one at the same time you register for GST/HST.
Step 3: Gather Your Registration Details
Have these ready before you start so you are not hunting for them mid-form:
Your business number, if you already have one
Your legal name, business name, and business structure (sole proprietor, partnership, or corporation)
Your Social Insurance Number (SIN) and basic personal details
Your fiscal year-end and estimated annual revenue
The effective date you want your registration to start
Step 4: Register Online Through Business Registration Online
The standard route is the CRA's Business Registration Online (BRO) service. As of late 2025 the CRA no longer takes GST/HST registrations by phone, so online is the way to go for almost everyone (a paper Form RC1 still exists for certain cases, such as some non-residents). Sign in through your CRA account or a sign-in partner, open BRO, and enter the business and personal details from Step 3.
Step 5: Set Your Reporting Period and Get Your GST/HST Number
You will add your GST/HST program account, which is your BN followed by RT0001 (for example, 123456789 RT0001), confirm your reporting period, and submit. Through BRO you typically get your GST/HST number right away, so you can start charging tax the same day.
Registering is the hard part done. Keeping the books clean afterward is where ReInvestWealth's AI Bookkeeper earns its keep, tracking the GST/HST you collect and pay automatically.
After You Register: What Comes Next
Getting the number is step one. Once you are registered, three things become part of your routine:
Charge and collect GST/HST on your taxable sales at the correct provincial rate.
File your GST/HST return on the schedule the CRA assigns you (annual, quarterly, or monthly, based on your revenue).
Remit what you collected to the CRA by your filing deadline, even for customers who have not paid you yet.
Your default filing frequency is set by your annual taxable revenue: most new registrants file annually, businesses over $1.5 million file at least quarterly, and those over $6 million file monthly. You can also elect to file more often if you prefer smaller, more frequent returns.
We kept this section short on purpose, because filing deserves its own walkthrough. For the full process, including payment methods and deadlines, read How to File and Pay GST/HST Online in Canada, or let ReInvestWealth file your sales tax for you.
One thing we hear often from new registrants: a filing period has to actually pass before a return shows up to be filed. If you register today, do not panic when there is nothing to file yet. That is normal.
A Quick Note on the Quick Method
If your revenue is modest, ask your accountant about the Quick Method of accounting. It is an optional election that lets eligible small businesses remit a lower, flat percentage of their GST/HST-included sales instead of tracking the tax on every single expense. It will not suit everyone, but for service businesses with few taxable purchases it can mean less paperwork and, sometimes, a bit less tax to remit. It is an election you make with the CRA, so it is worth raising when you register.
Keep Your Sales Tax Clean From Day One
Here is the honest truth about GST registration: the registration itself is quick. The part that trips people up is everything after, keeping track of what you collected, what you can claim back, and what you owe when a filing deadline rolls around.
That is exactly what ReInvestWealth's AI Bookkeeper was built for. It connects to your bank, categorizes your transactions, and keeps your GST/HST organized in the background so filing season is a five-minute review instead of a weekend project. It is built by CPAs, so the numbers are CPA-level clean, not just fast.
A few habits make the whole thing painless:
Watch your rolling revenue, not just your year-end total, so the $30,000 threshold never sneaks up on you.
Keep every business receipt, because each one may carry an input tax credit you can claim back. The Smart Shoebox (your digital receipt inbox) makes this automatic.
Set money aside as you collect it. The GST/HST you charge is not your revenue, it is tax you are holding for the CRA.
Connect your bank account and let the AI categorize your transactions, sales tax included. CPA-level clean books, 30-day free trial. Start for free.
Frequently Asked Questions
Do I need to register for GST/HST as a sole proprietor?
Yes, if your taxable revenue exceeds $30,000 over four consecutive calendar quarters (or in a single quarter). Sole proprietors register under their own business number, and the same $30,000 small supplier threshold applies whether you are incorporated or not.
How much does it cost to register for GST/HST?
Nothing. Registering for a GST/HST account with the CRA is a free service, whether you register online through Business Registration Online or by paper.
How long does it take to get a GST number?
If you register online through Business Registration Online, you typically receive your GST/HST number right away. The form itself takes most people about 15 to 20 minutes to complete.
Can I register for GST/HST voluntarily before I reach $30,000?
Yes. Voluntary registration lets you claim input tax credits on the GST/HST you pay for business expenses, which is often worth it if you are making sizable purchases. The trade-off is that you must start charging tax and filing returns once you register.
What happens if I register late?
You still owe the GST/HST you should have collected from your effective date of registration, even if you did not charge it to customers at the time. The CRA can also apply penalties and interest, so registering within the 29-day window matters.
Can I cancel my GST/HST registration if my business closes?
Yes. You notify the CRA of the closure and your effective closing date, file a final return, and they close the account. Keep your records afterward, since the CRA can review past filings.
Written by Maryam Ajorloo, CPA
> Maryam Ajorloo is the co-founder of ReInvestWealth and a CPA who specializes in small business tax, sales tax, and everyday bookkeeping. She helps entrepreneurs keep clean, audit-ready books and make sense of write-offs, filing deadlines, and the numbers behind their business. Read more · Connect on LinkedIn
Reviewed by Behdad Karimi Dermeni, CPA
> Co-founder of ReInvestWealth and a founding community builder at Stripe. Behdad built ReInvestWealth to give smart, busy entrepreneurs CPA-level accounting without the CPA-level price tag. Read more · Connect on LinkedIn
