GST and QST: when must a self-employed worker register?
A landscaper who bills $13,500 this summer, after a $12,000 spring: has he crossed the line? Maybe, without ever billing $30,000 in a single quarter. The small supplier threshold is calculated two ways, and the second one surprises many self-employed workers. Here, with the numbers, is when you must register for the GST and QST, from what date, and how to invoice afterwards.
The $30,000 threshold: what actually counts
Why a threshold? Businesses collect sales taxes on behalf of governments. To spare very small operations that paperwork, the law creates small supplier status: below the threshold, you don't have to register for or collect the GST (5%) and the QST (9.975%). You also need to be truly self-employed: if a client controls your schedule and your work, you may actually be an employee (see Employee or self-employed? The criteria that matter in Quebec).
The threshold is $30,000 in taxable supplies, and three details change everything:
- It's revenue, not profit. Expenses aren't deducted: a snow removal operator who bills $32,000 and keeps only $12,000 has crossed the threshold.
- Only taxable supplies count, worldwide, including zero-rated ones (taxable at 0%). Exempt supplies are left out.
- Your associates' sales are added in, for example those of another business you control.
The math is done by calendar quarter (January to March, April to June, July to September, October to December), whatever your fiscal year. If you're just starting out, keep the steps to becoming self-employed handy.
Two tests, four quarters: three real calculations
You stop being a small supplier if you go over $30,000 in a single calendar quarter, or in total over four consecutive calendar quarters. The first catches sudden big contracts; the second, gradual growth.
Example 1: the landscaper growing steadily
| Calendar quarter | Taxable sales | Running total |
|---|---|---|
| Oct. to Dec. 2025 | $4,000 | $4,000 |
| Jan. to Mar. 2026 | $3,000 | $7,000 |
| Apr. to June 2026 | $12,000 | $19,000 |
| July to Sept. 2026 | $13,500 | $32,500 |
No quarter goes over $30,000, but the four add up to $32,500 at the end of September 2026. According to the Canada Revenue Agency (CRA), when you go over across several quarters, your status ends at the end of the month following the quarter: here, October 31, 2026. October sales stay tax-free; he collects GST and QST no later than his first taxable sale after that date.
Example 2: the snow removal operator and the December contract
A snow removal operator bills $28,000 in residential contracts in October and November 2026. On December 5, he signs a store parking lot for $3,500, bringing the quarter to $31,500. He stops being a small supplier at the moment of that very sale and must collect tax on that contract. (We count amounts billed here; an accountant can confirm exactly when a sale counts.)
Example 3: the painter under the bar
A house painter bills $26,000 over her last four quarters, never more than $9,000 in a quarter. She remains a small supplier: she redoes the math every quarter and can consider voluntary registration.
You went over: the effective date and the 29-day deadline
The most misunderstood point: your obligation to collect starts on the effective date of your registration, not the day you register. According to the CRA, that date is no later than the day of the sale that puts you over (single-quarter test), or the day of your first taxable sale after your status ends (four-quarter test). You then have 29 days to register.
In Québec, Revenu Québec administers the GST as well as the QST, under the rules set by the federal government: registration, returns and payments for both taxes go through Revenu Québec. In practice:
- Write down the date of the sale that put you over, or the date your status ended.
- Register for both taxes with Revenu Québec without waiting for the 29 days to run out.
- Add the taxes to your invoices from the effective date, including the one that put you over if applicable.
- Put the taxes you collect in a separate account: that money isn't yours.
Exception: taxi and commercial ride-sharing drivers must register from the start, even below the threshold. For a special case (associates, sales outside Québec), Revenu Québec has the final word.
Voluntary registration: when it pays off
You can register below the threshold. The benefit: once registered, you recover the taxes paid on business purchases through input tax credits (ITCs) for the GST and input tax refunds (ITRs) for the QST. An unregistered small supplier pays those taxes and never sees them again.
Example: our painter buys $6,000 of paint and supplies and $4,000 of equipment during the year, before taxes. She pays $500 in GST and $997.50 in QST: $1,497.50 she could claim if she were registered and those purchases were used in her commercial activities. The flip side: her clients pay 14.975% more, and a $3,000 residential job becomes $3,449.25.
| Your situation | Likely effect of voluntary registration |
|---|---|
| Mostly commercial, registered clients | Often worth it: they recover the taxes you charge them, and you recover yours. |
| Mostly individual clients (residential cleaning, driveways) | Do the math: your tax-included price goes up 14.975%. |
| Lots of taxable purchases (materials, tools) | ITCs and ITRs carry more weight. |
Two constraints, according to Revenu Québec: registering for the QST means registering for the GST too, and you must stay registered for at least one year. According to the CRA, the effective date of a voluntary registration is usually the day you apply, or up to 30 days earlier. Since taxes change the price your client sees, reread Setting your hourly rate as a self-employed worker: the simple method and run the numbers with an accountant if your clientele is mixed.
Charging GST and QST correctly
The GST and the QST are both calculated on the price before taxes: the QST is not applied on top of the GST. For a $2,500 job, the GST is $125.00 (5%) and the QST is $249.375 (9.975%), rounded to $249.38, for a total of $2,874.38. Round to the nearest cent, going up from $0.005.
What the invoice must show depends on its amount; it's the information your registered client needs to claim their own ITCs and ITRs:
- Always: your name or business name, the date and the total amount.
- Amount of tax: from $100 (for the QST, at any amount).
- Your GST and QST registration numbers: from $100.
- Client's name and terms of payment: from $500.
- Description of the service: from $500 (for the QST, at any amount).
When you answer a request for quotes, say whether your price is "plus taxes." On GPP Emploi, the client pays you directly according to the schedule signed on the platform: if you're registered, each milestone invoice shows its taxes. The full process is explained on the self-employed workers page.
The Quick Method and returns: what comes after registering
Once registered, you report and remit the taxes you collect, minus your ITCs and ITRs. Your filing frequency appears on your confirmation of registration. An individual with business income, an annual filing frequency and a December 31 year-end has until June 15 to file, but must pay by April 30. Annual filers generally pay quarterly instalments.
The Quick Method simplifies the math: you remit a fixed percentage of your tax-included sales instead of claiming the taxes on most day-to-day expenses. For a service business: 3.6% for the GST and 6.6% for the QST. It's limited to businesses with annual taxable supplies of $400,000 or less, and off-limits to, among others, bookkeeping, tax return preparation, and legal or accounting services.
Example: a registered snow removal operator bills $60,000 before taxes and has used the Quick Method since the start of his fiscal year.
| Tax | Collected | Calculation | To remit |
|---|---|---|---|
| GST | $3,000.00 | $63,000 × 3.6% = $2,268.00, minus 1% of $30,000 | $1,968.00 |
| QST | $5,985.00 | $65,985 × 6.6% = $4,355.01, minus 1% of $31,421 | $4,040.80 |
He keeps $1,032.00 of GST and $1,944.20 of QST, which are added to his taxable income, but gives up ITCs and ITRs on day-to-day expenses (fuel, parts); those on capital property, such as a new snowblower, can still be claimed. If your taxable expenses are high, the regular method may pay more, and the election can only be revoked after a year: have an accountant run the comparison.
In short
- The threshold is $30,000 in taxable sales (revenue, not profit), by calendar quarter, including your associates' sales.
- Over in one quarter: taxes from the sale that puts you over. Over four quarters: status ends at the end of the following month.
- You have 29 days to register with Revenu Québec, but taxes are owed from the effective date.
- Voluntary registration lets you recover taxes on purchases and commits you for at least one year.
- On your invoices: both registration numbers, taxes shown separately and a description of the work. Ready to bid? Create your self-employed profile, it's free.
Frequently asked questions
Is the $30,000 GST/QST threshold based on net income?
No. You add up your taxable sales before any expenses. A self-employed worker who bills $31,000 and spends $20,000 has still crossed the small supplier threshold.
Do I register separately for the GST and the QST in Québec?
In Québec, Revenu Québec administers the GST as well as the QST: registration, returns and payments for both taxes are handled by Revenu Québec. A small supplier who voluntarily registers for the QST must also register for the GST.
Can a small supplier charge GST and QST?
No. Only a registered business collects these taxes, and it shows its registration numbers on invoices of $100 or more. If you want to charge taxes, for example to commercial clients, register voluntarily; you'll stay registered for at least one year.
What happens if I register late after going over the threshold?
Taxes are owed from the effective date of your registration, even if you didn't charge them. The longer you wait, the bigger the amount to sort out. Contact Revenu Québec quickly, ideally with an accountant's help.