GST/HST Registration Threshold Calculator
See whether the CRA's $30,000 small-supplier threshold has been crossed across rolling 4-quarter windows, and estimate whether voluntary registration would pay off given your customer mix and ITC recovery.
Last 5 Quarters of Taxable Supplies
Enter pre-tax revenue for each of the past 4 quarters plus the current quarter-to-date. Include all taxable supplies (zero-rated count, but exempt do not).
Still a Small Supplier
You remain a small supplier — neither any single quarter nor any rolling 4-quarter window exceeded $30,000. Registration is voluntary.
| Quarter | Revenue | Rolling 4Q Total | vs $30K |
|---|---|---|---|
| Q-4 | $4,000 | — | — |
| Q-3 | $5,000 | — | — |
| Q-2 | $6,000 | — | — |
| Q-1 | $7,000 | $22,000 | Under |
| Q0 | $8,000 | $26,000 | Under |
Voluntary Registration ROI — B2B
ITCs Recovered
+$2,000
Admin Cost
-$1,000
Net Annual
+$1,000
B2B customers recover the GST/HST you charge via their own Input Tax Credits, so charging tax adds no price pressure. You collect $2,000 in ITCs on your inputs and pay $1,000 in admin overhead.
Quick Method Preview (if registered)
With annual revenue of $26,000 ($29,380 tax-included), you're eligible for the Quick Method (under the $400,000 cap).
Regular Method Remittance
$3,380
Quick Method Remittance
$2,292
Quick Method Savings
$1,088
Comparison vs no-ITC baseline. Quick Method gives up the right to claim ITCs on most inputs, so real savings depend on how much GST you pay on business expenses.
How CRA's $30,000 test works: Aggregate your taxable supplies (and those of associated persons) over any four consecutive calendar quarters. If the rolling total exceeds $30,000 at any point, you cease to be a "small supplier" effective the end of the month following that quarter — and must register within 30 days. A single calendar quarter exceeding $30,000 is a faster trigger: you cease being a small supplier immediately in that quarter, and GST/HST applies to that quarter's revenue too.
Small Supplier Rules — What Counts and What Doesn't
Include in your $30,000 test: All taxable worldwide supplies (sales of taxable goods and services, including zero-rated supplies). Add the taxable supplies of any associated persons under ETA s.148(2).
Don't include: Exempt supplies (residential rent, most financial services, basic groceries), supplies made outside Canada that aren't connected to a Canadian permanent establishment, and the sale of capital property.
When threshold is crossed:
- Rolling 4-quarter breach: You cease to be a small supplier at the end of the month following that quarter. Register and start charging GST/HST by that date.
- Single-quarter spike: You cease to be a small supplier immediately in that quarter. GST/HST applies to the supply that pushed you over.
Voluntary registration: Small suppliers can register voluntarily to claim Input Tax Credits on business inputs. The trade-off is the GST/HST you collect from customers (a real cost if customers can't recover it) plus admin overhead. B2B businesses generally benefit; B2C businesses need ITC recovery that exceeds the price elasticity hit.
Frequently asked questions
When do I have to register for GST/HST in Canada?
If your taxable revenue from worldwide supplies exceeds $30,000 in any single calendar quarter or in any four consecutive calendar quarters (rolling), you are no longer a small supplier and must register within 30 days. The aggregation includes associated persons under ETA s.148.
Is voluntary GST/HST registration worth it?
It depends on your customer mix. B2B suppliers generally benefit because business customers recover the GST you charge via their own Input Tax Credits, while you recover GST you pay on inputs. B2C suppliers face price pressure since consumers cannot recover the tax — voluntary registration only pays off if your ITC recovery exceeds the price elasticity hit plus admin overhead.
What is the difference between the rolling 4-quarter test and the single-quarter test?
Both tests under ETA s.148(1) determine when you cease to be a small supplier. The rolling 4-quarter test sums your taxable supplies over any 4 consecutive calendar quarters; if the total exceeds $30,000, you must register by the end of the following month. The single-quarter test is faster: if any one quarter exceeds $30,000, you cease being a small supplier immediately in that quarter, and GST/HST applies to that quarter's revenue.
What is the Quick Method of Accounting?
A simplified GST/HST remittance method for businesses with annual tax-included revenue under $400,000. Instead of tracking ITCs on every purchase, you remit a flat percentage of tax-included sales (8.8% for HST13 services, 5.0% for HST15 retailers, etc.). You also get a 1% credit on the first $30,000 of tax-included supplies each fiscal year. Election is via Form GST74.
After registration
Once the account is open, follow the GST/HST return and NETFILE guide for reporting periods, access codes, nil returns, and electronic filing. When checking a supplier before claiming an ITC, use the GST/HST number verification guide.
Sources
Last updated May 2026. Reflects 2026 GST/HST rates and the $30,000 small-supplier threshold.
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