When the $30,000 small supplier limit applies, how the four-quarter test works, and what to do if you register late, with every rule linked to the CRA.
You have to register for GST once your taxable sales, together with those of any associated businesses, go over $30,000 in a single calendar quarter or over the last four consecutive calendar quarters. Below that you are a small supplier and registering is your choice. Once you go over, you have 29 days from your effective date of registration to register, and in Alberta you charge 5% GST with no provincial sales tax.
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What Is the $30,000 Small Supplier Rule?
The CRA calls a business under the limit a small supplier. A small supplier does not have to register for the GST/HST. Generally, everyone else who makes taxable sales, leases or other supplies in Canada does.
Three details decide which side of the line you are on:
- It is revenue, not profit. The test uses the total of your revenues before expenses from taxable supplies, including zero-rated supplies, made inside and outside Canada.
- Associated businesses count. If you are associated with other businesses, for example a corporation you control, their taxable revenues are added to yours.
- Some revenue is left out. Financial services, sales of capital property and goodwill from the sale of a business are not included in the total (CRA guide RC4022).
A calendar quarter is a three-month period starting on January 1, April 1, July 1 or October 1.
The rate in Alberta is 5% GST, with no provincial sales tax.
How Does the Four-Quarter Test Work?
The CRA applies two tests at the same time: your taxable revenues in any single calendar quarter, and your total over the last four consecutive calendar quarters. Going over $30,000 on either one ends your small supplier status, but the two cases start at different times:
$30,000 or less
- You are a small supplier.
- You do not have to register.
- You can register voluntarily.
Over $30,000 in one quarter
- You stop being a small supplier with the sale that takes you over.
- Charge GST on that sale.
- Register within 29 days.
Over $30,000 across four quarters
- You stay a small supplier until the end of the following month.
- Charge GST from your first sale after that.
- Register within 29 days.
In both cases you must register within 29 days of your effective date of registration. Charging GST does not wait for the registration: the CRA expects it on the sale that took you over the limit (case 2) or from your first sale after you stopped being a small supplier (case 3).
Say a Calgary consultant bills $18,000 from January to March 2026 and $16,000 from April to June 2026. Neither quarter is over $30,000, but together they come to $34,000. Under the CRA’s rule the consultant stays a small supplier until July 31, 2026, the end of the month after the quarter in which the limit was passed. The first sale after that is the effective date of registration: GST is charged on it, and the consultant has 29 days from that date to register.
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Should You Register Voluntarily?
A small supplier that makes taxable sales can choose to register. The main reason to do it is input tax credits (ITCs): once registered, you can generally recover the GST/HST you pay on purchases and expenses used in your business, such as rent, office expenses, telephone and utilities, and accounting and legal fees. If you do not register, you do not charge GST/HST (other than on certain sales of real property) and you cannot claim ITCs.
Registering also brings obligations. You have to:
- charge, collect and remit GST/HST on your taxable sales,
- file GST/HST returns for every reporting period, even when you have nothing to report, and
- stay registered for at least one year before you can cancel, unless you stop your commercial activities.
When you register as a small supplier, your effective date of registration is usually the day you ask for your GST/HST account, and it can generally be up to 30 days before that day. A corporation’s effective date cannot be earlier than its incorporation date.
Whether it pays off depends on who your customers are and how much GST/HST you pay on costs. Customers that are GST/HST registrants can generally claim the GST you charge them as their own ITCs; consumers cannot. Once you are registered, also look at the GST/HST quick method. It is open to most businesses with $400,000 or less a year in taxable sales, GST/HST included, and lets you remit a set percentage of your sales instead of working out the GST/HST paid on every expense.
What Happens If You Register Late?
The obligation starts when you stop being a small supplier, not when the CRA issues your number. The CRA’s registrant guide is direct about it: if you were required to charge GST/HST but did not, you are still liable for the tax, and you include it in your return for the period in which you should have charged it. In practice, GST you never collected from your customers can come out of your own pocket.
Late returns cost more on top of that:
- Late-filing penalty. If you file after the due date and owe money, the penalty is 1% of the amount owing plus 25% of that 1% for each complete month the return is late, up to 12 months.
- Interest. The CRA charges interest on overdue amounts at its basic rate plus 4% (RC4022).
- Paper returns. Almost every registrant must file electronically, and a paper return can draw a penalty.
For what a missed payment can mean in practice, see our guide to the impact of late GST payments.
How Do You Register for a GST Number?
Most businesses register online through Business Registration Online (BRO). If you do not have a business number (BN) yet, you get one at the same time as your GST/HST account. Have this ready:
- your effective date of registration,
- your fiscal year for GST/HST,
- your total annual revenue, and
- basic personal and business information.
You need a CRA account to use BRO. Save or print your BN during the session, because it is not sent to you. If you cannot use BRO, the CRA offers other ways to register, such as Form RC1.
How Often Will You File GST Returns?
The CRA assigns your reporting period from your annual taxable supplies, and you can choose to file more often.
| Annual taxable supplies | Assigned period | You can choose |
|---|---|---|
| $1,500,000 or less | Annual | Monthly or quarterly |
| More than $1,500,000 up to $6,000,000 | Quarterly | Monthly |
| More than $6,000,000 | Monthly | No other option |
- Annual filers. For most businesses, the return and final payment are due three months after the fiscal year-end. A sole proprietor with a December 31 year-end and business income for the year pays by April 30 and files by June 15.
- Monthly and quarterly filers. The return and payment are due one month after the end of each reporting period.
- Nothing to report. You still file a return for every period, called a nil return.
How Can We Help With GST?
We prepare and file GST returns for Alberta small businesses from our Calgary office. GST/HST filing is included in our Foundation, Growth and Scale bookkeeping plans, listed on our pricing page. A GST/HST return on its own starts from $150 per filing period. Fees exclude GST.
If you sell online, our guide to GST filing for e-commerce businesses covers the rates for customers in other provinces.
Frequently Asked Questions
Do I charge GST if my sales are under $30,000?
Not if you stay a small supplier and choose not to register. Without a registration you do not charge GST/HST (other than on certain sales of real property), and you cannot claim input tax credits.
Is the $30,000 limit based on revenue or profit?
Revenue. The CRA counts your revenues before expenses from worldwide taxable supplies, including zero-rated supplies, plus those of associated businesses. Financial services, sales of capital property and goodwill from selling a business are left out.
What GST rate do I charge in Alberta?
Alberta has 5% GST and no provincial sales tax. Sales to customers in other provinces can carry a different rate, because the rate depends on where the supply is made.
How long do I have to register once I go over $30,000?
29 days from your effective date of registration. That date is the day of the sale that took you over $30,000 in one quarter, or your first sale after you stopped being a small supplier under the four-quarter test.
Can I cancel a voluntary registration later?
Yes, if you are a small supplier and you have been registered for at least one year, or if you close the business or stop making taxable supplies.
Reviewed on 17 October 2026. Thresholds, rates, deadlines and penalties in this article are from the Canada Revenue Agency, linked beside each fact and listed below.
Bookkeeping
Monthly cloud bookkeeping, with bank and credit card reconciliation, monthly reports and GST/HST filing included
T2 Corporate Tax
Every Canadian corporation must file a T2 within six months of fiscal year-end, active or inactive
Sources
- Canada Revenue Agency, When to register for and start charging the GST/HST (page dated 2026-06-16, checked 17 October 2026)
- Canada Revenue Agency, Register voluntarily for a GST/HST account (page dated 2026-01-14, checked 17 October 2026)
- Canada Revenue Agency, Register for a GST/HST account (page dated 2026-07-20, checked 17 October 2026)
- Canada Revenue Agency, General Information for GST/HST Registrants (RC4022) (Rev. 25, checked 17 October 2026)
- Canada Revenue Agency, Input tax credits (page dated 2026-10-14, checked 17 October 2026)
- Canada Revenue Agency, GST/HST calculator (and rates) (page dated 2025-04-01, checked 17 October 2026)
- Canada Revenue Agency, Reporting requirements and deadlines (File your GST/HST return) (page dated 2026-05-13, checked 17 October 2026)
- Canada Revenue Agency, GST/HST filing penalties (page dated 2025-06-16, checked 17 October 2026)
