GST/QST return: what is your filing deadline in 2026?
In Quebec in 2026, your GST and QST return must reach Revenu Québec no later than one month after the end of your reporting period if you file monthly or quarterly. For the July to September 2026 quarter, the October 31 deadline falls on a Saturday, so it moves to Monday, November 2, 2026.
This is the deadline self-employed workers and small registered businesses forget most often, because it lines up with neither tax season nor year-end. Yet late penalties start on day one: up to 15% of the QST amount you have to remit. Here are all the deadlines by filing frequency, how to calculate the amount to remit, and what being late really costs.
Calculate your net tax before you file: add up the GST and QST you collected, subtract your input tax credits and refunds, and check every invoice with our GST QST calculator. An exact net amount avoids reassessments and interest.
What is the deadline for a quarterly GST/QST return in 2026?
For a quarterly reporting period, Revenu Québec's rule is simple: the return and the payment must arrive no later than one month after the last day of the quarter. For a calendar-year fiscal period, the four deadlines form an easy calendar to remember, with two weekend shifts in 2026-2027.
| 2026 quarter | Reporting period | Deadline | Actual day in 2026-2027 |
|---|---|---|---|
| Q1 | January 1 to March 31 | April 30, 2026 | Thursday, April 30, 2026 |
| Q2 | April 1 to June 30 | July 31, 2026 | Friday, July 31, 2026 |
| Q3 | July 1 to September 30 | October 31, 2026 | Saturday: moved to Monday, November 2, 2026 |
| Q4 | October 1 to December 31 | January 31, 2027 | Sunday: moved to Monday, February 1, 2027 |
The weekend shift is not a favour from your accountant: Revenu Québec and the Canada Revenue Agency both provide that when your deadline falls on a Saturday, a Sunday or a holiday, it extends to the next business day. The same shift applies to monthly filers: the September 2026 period, normally due October 31 as well, therefore ends on Monday, November 2, 2026. Watch your financial institution's processing times, though: a payment started on the evening of November 2 may only be processed the next day.
What is your deadline if you file your GST/QST once a year?
If your filing frequency is annual, your return must generally reach Revenu Québec no later than three months after the end of your fiscal year. For a year ending December 31, 2026, a corporation therefore has until March 31, 2027 to file and pay. Your frequency is not a free choice at the start: it is assigned based on your annual taxable sales, and you can then ask to file more often.
| Annual taxable sales | Assigned frequency | Other frequency available |
|---|---|---|
| $1,500,000 or less | Annual | Monthly or quarterly |
| Over $1,500,000 to $6,000,000 | Quarterly | Monthly |
| Over $6,000,000 | Monthly | None |
The most important exception covers individuals in business: if you have business income, an annual reporting period and a fiscal year ending December 31, you have until June 15, 2027 to file your return, but any GST or QST owing is still due no later than April 30, 2027. Filing in June without having paid in April therefore exposes the balance to interest and penalties, even if the return itself is on time.
Annual filers face another trap: instalments. If your estimated net tax for the current year is $3,000 or more, and last year's net tax was also $3,000 or more, you must make four instalment payments, each due no later than one month after the end of a quarter of your fiscal year. For the 2026 calendar year, the Q3 instalment therefore follows the same deadline shifted to November 2, 2026. Add these dates to your year-end tax moves for 2026 checklist before December arrives.
How much GST/QST do you actually remit for one quarter?
You remit net tax: the taxes you collected on your taxable sales, minus the input tax credits (ITCs) for GST and input tax refunds (ITRs) for QST that you paid on your business expenses. Here is an example calculated for this article, for the July to September 2026 quarter of a Quebec self-employed worker.
| Item for the quarter | GST at 5% | QST at 9.975% | Total |
|---|---|---|---|
| Tax collected on $80,000 of taxable sales | $4,000 | $7,980 | $11,980 |
| Tax paid on $20,000 of taxable expenses | −$1,000 | −$1,995 | −$2,995 |
| Net tax to remit to Revenu Québec | $3,000 | $5,985 | $8,985 |
Three details often change the result. First, invoiced amounts are what count, not just amounts collected: an invoice issued in September belongs to the quarter even if the client pays in November. Second, every ITC and ITR needs supporting documents showing the tax paid. Third, if your credits exceed the tax collected — during a quarter when you invest heavily, for example — the result is a refund, but the return is still due on the same deadline. Redo the calculation line by line in our GST QST calculator, then use the same fiscal year to estimate the income tax that follows with our Quebec income tax calculator.
How much does a late GST/QST return cost in Quebec?
Being late is charged separately for each tax, and the two systems do not work the same way. For QST, Revenu Québec charges a penalty on the amount to remit based on how late you are: 7% if the delay is 7 days or less, 11% if it is over 7 days but no more than 14 days, and 15% if it is over 14 days. For GST, the late-filing penalty is 1% of the amount owing, plus 0.25% for each complete month the return is late, up to 12 months — except when the balance is nil or a refund is owed. Interest is added under both systems.
| Delay, on the $8,985 example | QST penalty (on $5,985) | GST penalty (on $3,000) | Total penalties |
|---|---|---|---|
| 1 to 7 days | 7% = $418.95 | n/a (no complete month) | At least $418.95 |
| 8 to 14 days | 11% = $658.35 | n/a (no complete month) | At least $658.35 |
| Over 14 days | 15% = $897.75 | 1% = $30.00 after one complete month, plus 0.25% per month | $897.75 and up |
The lesson from this in-house table: on the QST side, the bill climbs in steps from the very first week, long before the first complete month. One forgotten week on an ordinary quarter therefore costs over $400 before interest — several hours of billable work gone. Conversely, filing on time even when you cannot pay everything cuts the filing penalty: only the interest and the payment side remain to manage, not both piles at once.
What can you do if you cannot pay your GST/QST on time?
File your return by the deadline anyway, even if you cannot pay the full balance, and even if you had no business activity in the period: the CRA requires a return for every reporting period, including a nil return. Filing on time stops the filing penalty and shows good faith; the payment itself can be negotiated.
Revenu Québec allows you, under certain conditions, to enter into an instalment payment agreement if your financial situation does not let you pay your balance in a single payment. Two practical payment rules are worth remembering: if the GST or QST amount to remit is $10,000 or more, the payment must be made electronically, and the date that counts is the date your financial institution processes the payment, not the date you click. So start the payment at least one business day before the deadline — especially when, like November 2, 2026, the shifted deadline lands on a Monday after a weekend.
In short: one month after the end of your period, three months for annual filers, payment on April 30 and filing on June 15 for an annual-frequency individual in business. Write down the four quarterly dates now — April 30, July 31, October 31 and January 31, with their weekend shifts — and the October 31 to Monday, November 2, 2026 shift becomes a simple calendar appointment instead of a 15% penalty.
Frequently asked questions
What is the deadline for the Q3 2026 GST/QST return?
For the period from July 1 to September 30, 2026, the normal deadline is October 31, 2026, one month after the end of the quarter. But October 31, 2026 falls on a Saturday, so Revenu Québec extends the deadline to the next business day, Monday, November 2, 2026. Both the return and the payment must arrive by November 2 at the latest, allowing for your bank's processing times.
Is a GST/QST deadline extended when it falls on a weekend?
Yes. Revenu Québec provides that when your deadline to file a return or make a payment expires on a Saturday, a Sunday or a holiday, it is extended to the first following day that is not a Saturday, a Sunday or a holiday. That is what moves the October 31, 2026 deadline to Monday, November 2, 2026, and the January 31, 2027 deadline, a Sunday, to Monday, February 1, 2027.
What is the penalty for filing a QST return late?
For QST, the penalty is calculated on the amount to remit: 7% if the delay is 7 days or less, 11% if it is over 7 days but no more than 14 days, and 15% if it is over 14 days. Interest is added to the unpaid balance. On net QST of $5,985, a delay over 14 days therefore costs $897.75 in penalties before interest, which makes the one-month deadline easy to justify.
Does a self-employed annual filer have to pay GST/QST by April 30 or June 15?
Both dates matter, but for different things. If you are an individual with business income, an annual reporting period and a fiscal year ending December 31, you have until June 15 of the following year to file your GST/QST return. However, any amount owing must be remitted no later than April 30. Paying in June therefore exposes the balance to interest and penalties, even with a return filed on time.
Do I have to file a GST/QST return if I sold nothing in the quarter?
Yes. A registrant must file a return for every reporting period, even with no business activity, no income and no net tax to remit: that is a nil return. The same obligation applies to the period in which you close your GST/QST account, with a final return. Skipping a quiet period does not make the deadline disappear: it only risks a request to file and penalties later.
How do I know whether my GST/QST filing frequency is monthly, quarterly or annual?
Your frequency is assigned when you register, based on your expected total annual taxable sales: $1,500,000 or less gives an annual frequency, over $1,500,000 to $6,000,000 gives a quarterly frequency, and over $6,000,000 gives a monthly frequency. It appears on your registration confirmation and in My Account for businesses. You can ask to file more often, for example to receive your refunds sooner.