When must I register for GST/HST? The $30,000 rule explained

Arsen Accounting Services · Sources checked October 27, 2026

For many small businesses, GST/HST registration becomes mandatory when taxable sales exceed the $30,000 small-supplier threshold. The timing matters: exceeding it within one calendar quarter is different from exceeding it across several consecutive quarters. Waiting for your annual income-tax return can mean discovering the requirement too late.

Use taxable revenue, not profit

The calculation generally uses revenue before expenses from worldwide taxable supplies, including zero-rated supplies. For a sole proprietor, consider all businesses and relevant associated persons, not just one trading name. Exempt supplies and exclusions such as sales of capital property require separate attention. This guide addresses the ordinary small-business test; charities and public service bodies have different rules. CRA — Small suppliers, GST/HST Memorandum 2-2

Prepare calendar-quarter totals: January–March, April–June, July–September and October–December. Keep the current quarter visible as it grows, as well as the rolling four-quarter total. A low profit margin does not itself keep taxable sales below the threshold.

Two ways to cross the threshold

More than $30,000 in one calendar quarter

You stop being a small supplier on the sale that takes you over the limit. GST/HST applies to that sale, and registration must be completed within 29 days of the effective registration date. CRA — When to register and start charging GST/HST

More than $30,000 over four or fewer consecutive quarters

If no single quarter exceeds $30,000, small-supplier status ends at the end of the month following the quarter in which the combined total exceeds the threshold. Registration takes effect no later than your first supply after that point, with registration required within 29 days of the effective date. CRA — When to register and start charging GST/HST

For illustration, suppose taxable sales for the four quarters ending September total $32,000 and none exceeds $30,000 alone. Under the ordinary rule, small-supplier status ends October 31. A first taxable supply on November 1 would require GST/HST. Confirm your actual dates and transaction types before applying this example.

Check exceptions before relying on the limit

Taxi operators and commercial ride-sharing drivers must generally register from the start of their taxable passenger-transportation activity, even as small suppliers. Do not assume every platform activity uses the same rule. If you should already have registered, CRA has a process for requesting an earlier effective date; review the transactions involved promptly. CRA — Register for a GST/HST account

Understand what registration changes

Voluntary registration may be available below the threshold. It brings collection and filing responsibilities, and may allow input tax credits for eligible GST/HST paid on business inputs. Eligibility and documentation must be checked; registration is not automatically advantageous for every business. CRA — Voluntary GST/HST registration

Once registered, you generally file for each reporting period, including a period with no activity. A nil return is still a return. Confirm your assigned reporting period rather than assuming GST/HST is filed with your personal income-tax return. CRA — GST/HST reporting requirements and deadlines

Common questions

Does a new business name give me another $30,000 limit?

Not by itself. The calculation follows the person and the applicable association rules, rather than giving each sole-proprietor business name a fresh threshold. CRA — Small suppliers, GST/HST Memorandum 2-2

What should I bring for a registration review?

Bring dated sales summaries by activity, customer locations, information about exempt or zero-rated supplies, invoices around the crossing date and details of any existing GST/HST account.

Get the effective date right

Arsen Accounting can discuss GST/HST return preparation and the registration questions relevant to the engagement. Mention whether you have already charged tax, when sales increased and which returns remain outstanding.

Discuss your tax preparation