Do I Need to Register for GST/HST? The $30K Threshold Explained

Most new businesses don’t need to register immediately — but the clock starts earlier than you think.

The short answer

You must register once you exceed $30,000 in taxable revenues

If your total taxable revenues are $30,000 or less over the last four consecutive calendar quarters — and you didn’t exceed $30,000 in any single quarter — you are a “small supplier” and are not required to register for GST/HST. The moment you exceed $30,000, you must register within 29 days and begin collecting GST/HST on sales from that point forward.

You can also register voluntarily at any time below the threshold — and there are good reasons to do so early. Registered businesses can claim Input Tax Credits (ITCs) to recover the GST/HST they pay on business expenses. If you’re spending on equipment, software, or services for your business, voluntary registration often pays for itself.

How it works

How the $30,000 threshold is calculated

The threshold is measured over four consecutive calendar quarters. A calendar quarter is January–March, April–June, July–September, or October–December. “Four consecutive quarters” means any rolling four-quarter window — not just a calendar year.

Two ways to hit the threshold

Trigger 1 — Four-quarter rolling total

Your taxable revenues over any four consecutive calendar quarters exceed $30,000. This catches steady earners who haven’t had a single big quarter but are consistently earning.

Trigger 2 — Single quarter exceeds $30,000

Your taxable revenues in a single calendar quarter exceed $30,000. One large contract can trigger registration immediately, even if the rest of the year is quiet.

What counts toward the $30,000

Counts toward the threshold

  • Taxable supplies of goods and services made in Canada
  • Zero-rated supplies (e.g., exports — they're taxable at 0%, but still count)
  • Revenues from all your business activities combined (not just one stream)
  • Revenues from associated businesses under common ownership or control

Does NOT count

  • Exempt supplies (residential rent, most healthcare, financial services, etc.)
  • Sale of capital property (e.g., selling your business vehicle)
  • Goodwill from a business sale

The rolling window in practice

Scenario A — Steady freelancer crossing the threshold

QuarterRevenue4-quarter totalStatus
Q1 (Jan–Mar)$7,500$7,500Under threshold
Q2 (Apr–Jun)$8,000$15,500Under threshold
Q3 (Jul–Sep)$8,500$24,000Under threshold
Q4 (Oct–Dec)$7,000$31,000Must register

The moment the Q4 revenue tips the four-quarter total over $30,000, the 29-day registration clock starts.

Scenario B — Single large contract triggers immediate registration

QuarterRevenue4-quarter totalStatus
Q1 (Jan–Mar)$4,000$4,000Under threshold
Q2 (Apr–Jun)$32,000$36,000Must register
Q3 (Jul–Sep)
Q4 (Oct–Dec)

The $32,000 Q2 alone exceeds $30,000 in a single quarter — triggering registration regardless of the four-quarter total.

The 29-day registration deadline

Once you exceed $30,000, you have 29 days to register with the CRA. You must start collecting GST/HST on all taxable sales made after the day you exceeded the threshold — not just after you register. If you invoice a customer on day 5 and don’t register until day 25, you still owe the GST/HST on that day-5 invoice. The registration date does not reset your obligation.

Why register voluntarily before you hit $30,000

Voluntary registration is allowed at any revenue level. The main benefit is Input Tax Credits (ITCs) — you can claim back the GST/HST you paid on business expenses like software subscriptions, equipment, professional services, and office supplies.

If you spend $10,000/year on taxable business expenses, you’re paying roughly $1,300 in GST/HST on those purchases. As a registered business, you get that back when you file. As an unregistered small supplier, it’s just a cost.

One downside: once registered, you must charge GST/HST on all taxable sales and file returns on schedule. You can’t selectively apply it.

Free tool

Calculate your exact rate

Use our free Canadian sales tax calculator to get the answer for your specific situation — seller province, buyer province, and product type — with government sources cited.

Use the free calculator

What happens after you register

  • 1

    Charge GST/HST on taxable sales

    Add GST or HST (depending on the customer's province) to all taxable invoices. The rate follows the customer's province — not yours.

  • 2

    Track GST/HST collected and paid

    Keep records of all GST/HST you collect from customers (tax collected) and all GST/HST you pay on business expenses (ITCs). The difference is what you remit.

  • 3

    File returns and remit on schedule

    Most new registrants file annually. Once your taxable revenues exceed $1.5M you must file quarterly; over $6M you file monthly. Electronic filing is mandatory as of January 1, 2024 for most registrants.

  • 4

    Consider the Quick Method

    Businesses with $400,000 or less in annual taxable supplies (including GST/HST) can use the Quick Method — a simplified remittance calculation that can reduce paperwork. Not available to accountants, tax preparers, financial consultants, or lawyers.

What most people get wrong

Common GST/HST registration mistakes

Thinking the threshold resets every calendar year

It doesn't. The four-quarter window is rolling, not annual. If you earned $8,000 in each of Q3 and Q4 last year and $8,000 in each of Q1 and Q2 this year, your four-quarter total is $32,000 even though no calendar year exceeded $30,000. The window is always the most recent four consecutive quarters.

Forgetting that zero-rated revenues count toward the threshold

Zero-rated supplies (exports, basic groceries, prescription drugs) are taxed at 0% GST — but they still count as taxable supplies for threshold purposes. A business that exports $35,000 of goods annually is over the threshold and must register, even though they charge 0% GST on every invoice.

Waiting until after you register to start collecting

The obligation to collect GST/HST starts on the day you exceed the threshold — not the day you register. If you invoice $31,000 on March 15 and register on April 5, you owe GST/HST on the March 15 invoice. The CRA can assess back taxes on sales made after the threshold was crossed, even if you hadn't registered yet.

Treating the $30,000 threshold as a per-business-activity limit

The threshold applies to your total taxable revenues across all business activities. If you have a freelance writing business earning $18,000 and a photography side business earning $14,000, your combined total is $32,000 — over the threshold. You can't split them to stay under.

Thinking GST registration covers provincial taxes

Your CRA GST/HST number does not give you authority to collect BC PST, SK PST, MB RST, or QC QST. Those require separate registrations with provincial authorities. Once you're GST-registered, you still need to check whether any of your sales trigger provincial tax obligations — and register separately with each relevant province.

Not registering voluntarily to claim ITCs on startup costs

If you're spending money to build a business before revenue starts — on equipment, software, legal fees, design — you're paying GST/HST on all of it. Registering voluntarily before you hit $30,000 lets you claim ITCs on those startup expenses. Many new businesses leave thousands of dollars in recoverable tax on the table by waiting until they're forced to register.

Summary

Key takeaways

  • You must register for GST/HST once taxable revenues exceed $30,000 over four consecutive calendar quarters OR in a single quarter.

  • You have 29 days from the day you cross the threshold to register.

  • The obligation to collect begins on the day you cross the threshold — not the day you register.

  • Zero-rated revenues (exports, basic groceries) count toward the $30,000 even though GST is charged at 0%.

  • Exempt revenues (residential rent, most healthcare) do NOT count toward the threshold.

  • The four-quarter window is rolling — it is not reset by a new calendar year.

  • Associated businesses under common control count their revenues together for threshold purposes.

  • Voluntary registration is allowed at any revenue level and lets you claim ITCs on business expenses.

  • Your CRA GST/HST number does not cover provincial taxes. BC, SK, MB, and QC require separate registrations.

Free tool

Calculate your exact rate

Use our free Canadian sales tax calculator to get the answer for your specific situation — seller province, buyer province, and product type — with government sources cited.

Use the free calculator

Government sources

Sources

The registration thresholds and rules in this article are sourced directly from official CRA publications. Verify current requirements before filing.

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Disclaimer

TaxMapCA provides tax information, not tax advice. This article is for general informational purposes only and does not constitute legal or accounting advice. GST/HST registration rules have specific exceptions for certain business types and associated corporations not fully covered here — always verify your specific situation against the CRA sources linked above. TaxMapCA is not affiliated with or endorsed by the Canada Revenue Agency or any government agency. For complex situations, consult a qualified CPA or tax professional.