The GST is the federal goods and services tax. The QST is the Quebec sales tax. In Quebec, Revenu Québec administers both: you register, file and pay in one place.
Just getting started? The other steps for your first year are gathered in our guide to a self-employed person's obligations in Quebec.
What counts toward the $30,000 threshold?
The threshold is based on your taxable sales, meaning the sales the tax applies to, even at a 0% rate. It isn't based on your profit.
What counts | What doesn't count |
|---|---|
Your sales of goods and services, your rentals, exchanges and barters | The GST and QST themselves |
Your sales to all your customers, wherever they are in the world | Financial services |
Your sales taxed at 0% (called "zero-rated") | Sales of the business's long-lasting assets, such as a computer or a vehicle, and of its client base |
The sales of businesses "associated" with you, for example a corporation you control | Exempt sales, meaning sales that aren't taxable |
What this means for you. A $12,000 contract counts for $12,000, even if you spent $4,000 to deliver it. And the calculation is done by calendar quarter: January to March, April to June, July to September, October to December.
When do you have to register, at the latest?
It all depends on how you cross the threshold, and the deadlines aren't the same for the GST and for the QST.
Your situation | You must collect the taxes | You must apply for registration |
|---|---|---|
You exceed $30,000 in a single quarter | Starting with the sale that takes you over the threshold | QST: before that sale. GST: within 29 days after it. |
You exceed $30,000 over four consecutive quarters, without exceeding it in any single one | No later than the day after the end of the month following the quarter in which you went over | QST: before your first taxable sale from that date. GST: within 29 days after that date. |
What to do. The QST deadline is the shortest. So the simplest approach is to register for both taxes at the same time, as soon as you see the threshold coming. A big contract on the horizon? Register before you send it.
Fictional example: when does Léa start charging the taxes?
Fictional example: the name and amounts are made up to illustrate the rule.
Léa is a web designer. She starts her business in January 2026 and records her sales every quarter.
2026 quarter | Sales for the quarter | Total for the last four quarters |
|---|---|---|
January to March | $6,000 | $6,000 |
April to June | $9,000 | $15,000 |
July to September | $8,000 | $23,000 |
October to December | $9,500 | $32,500 |
No single quarter exceeds $30,000. But on December 31, 2026, the four quarters together exceed the threshold. Léa remains a small supplier until the end of the following month, January 31, 2027. She must charge the GST and QST starting February 1, 2027, at the latest.
For the QST, she applies for registration before her first taxable invoice in February. For the GST, she has 29 days from that date. In practice, she does both in January.
Another scenario, just as fictional: if Léa had invoiced a single $35,000 contract in May, she would have exceeded the threshold in a single quarter. The taxes would have applied to that very contract.
Is it worth registering before you have to?
Even below the threshold, you can choose to register. Here's what that choice changes.
What you gain | What you accept |
|---|---|
You recover the GST and QST you pay on your business purchases. These are called input tax credits (ITCs) for the GST and input tax refunds (ITRs) for the QST. | You charge the taxes on all your taxable sales. |
You no longer have to keep a close eye on the threshold. | You file a return for every period. |
You stay registered for at least one year. Registering for the QST also requires registering for the GST. |
What this means for you. The decision depends mostly on your customers and your purchases. If you sell to individuals, the taxes increase their bill. If you buy a lot of equipment for your business, recovering the taxes can make a difference. Run the numbers with your own figures before you decide.
Two situations rule out registration: an activity carried on without a reasonable expectation of profit, and an activity that sells only exempt goods or services.
When do you have to register from the very first dollar?
In some cases, the $30,000 threshold doesn't apply at all.
- Taxis and commercial ridesharing. If you operate a taxi, or if you drive passengers for an app like Uber or Lyft, you must register for the GST and QST from the day you start.
- Admission tickets sold by a non-resident. A person who doesn't reside in Quebec (or in Canada, for the GST) and who sells admissions to an event in Quebec directly to the public must also register.
- QST only. You must register for the QST, even as a small supplier, if you sell tobacco or fuel at retail, if you sell alcoholic beverages (except under a reunion permit), if you sell or lease new tires, or if you sell road vehicles (other than your own business vehicles) or lease them for 12 months or more.
How do you register, step by step?
- Choose the right Revenu Québec service.
- You don't have a business file yet, even though you've been working for a while? Use the online service for registering a start-up business (Inscription d'une entreprise en démarrage). It also lets you open your other business files if needed, for example for source deductions.
- You already have a file? Go through My Account for businesses, Taxes section.
- Prefer paper? Fill out the Application for Registration form (LM-1).
- Choose your reporting periods. You can choose them when you register. Usually, the fiscal year used for the taxes matches your taxation year for income tax. Revenu Québec then assigns a filing frequency (monthly, quarterly or annual) based on your total annual taxable sales in Canada.
- Keep the confirmation. It shows how often you'll have to file.
Do you also sell to customers in other provinces? Note that a GST registration also covers the HST, the harmonized sales tax used in some provinces.
After you register: collect, report, keep records
Registration is only the beginning. It starts a cycle that repeats every period: you collect the taxes, you report them, you keep the proof.
Collect: how much should you charge?
The GST is 5% and the QST is 9.975%. Both are calculated on the same selling price: the QST doesn't apply to the GST.
Fictional example: for a $1,000 invoice for services, you add $50.00 of GST and $99.75 of QST. Your customer pays $1,149.75.
You still need to show these taxes correctly on your invoices: see what a self-employed person's invoice must include.
What this means for you. The taxes you collect don't belong to you. Set them aside until the remittance date.
Report: when and how?
You file a single return for the GST and QST, electronically: this has been mandatory for almost all registrants since January 1, 2024.
The calculation is simple in principle. You add up the taxes you charged your customers during the period. You subtract the taxes you paid on your business purchases (your ITCs and ITRs). If the result is positive, you pay it. If it's negative, Revenu Québec refunds you.
Your filing frequency | Return due | Payment |
|---|---|---|
Monthly or quarterly | One month after the end of the period | With the return |
Annual, general case | Three months after the end of the fiscal year | With the return, plus instalments (partial payments) during the year, if applicable |
Annual, self-employed person whose fiscal year ends on December 31 | No later than June 15 of the following year | No later than April 30 of the following year |
If you file once a year, you generally have to pay four GST and QST instalments. Each one is due no later than the last day of the month following a quarter of your fiscal year.
Small businesses can also, under certain conditions, use the Quick Method to calculate the taxes they remit. It's worth looking at with your real figures.
Keep records: what should you keep, and for how long?
At the federal level, the rule is to keep your records and supporting documents for six years after the end of the last year they relate to, including your GST records. They must be kept in Canada. Accurate digital copies are accepted.
What to do. File every sales invoice and every purchase receipt by reporting period. Your net tax calculation then becomes a simple sum, not an investigation.
Frequently asked questions
Do I also need to register with the Canada Revenue Agency (CRA) for the GST?
No, not separately in most cases. In Quebec, Revenu Québec administers the GST as well as the QST. Its registration services, online or with form LM-1, register you for both taxes at once. You then file a single return for both taxes, in one place, for every reporting period.
Do I have to file a return if I sold nothing during the period?
Yes. Once you're registered, you must file your GST and QST return for every period, even if you have no tax to pay and no refund to claim. A period with no sales gives you a nil return, but you still have to file it electronically before the deadline.
I went over the threshold without registering: what should I do?
Act quickly. The returns for past periods still have to be filed. Revenu Québec lets you correct your situation through a voluntary disclosure: if your request is accepted, some penalties and interest may be reduced. Start by gathering your invoices from the date you went over the threshold. Bringing past periods up to date is handled separately, with a scope defined at the outset.
Can I cancel a voluntary registration?
Yes, but not right away. If you registered by choice, as a small supplier, you must stay registered for the GST and QST for at least one year. After that, you can request the cancellation of your registration. Take stock of your sales before you request it.
Let Alta Conseils handle your GST and QST
Alta Conseils handles this cycle for self-employed people and small and medium-sized businesses. We track the $30,000 threshold with you, keep your books, calculate your net taxes and prepare your GST and QST returns for every period. Discover our Bookkeeping service, or talk to us about where you stand.
