What Happens If You File Your GST/HST Return Late in Canada

Missing a GST/HST filing deadline is not the disaster most business owners imagine — but it is a meter that starts running the day after the due date, and the meter has two hands. The penalty attaches to the late return; interest attaches to the unpaid balance. Understanding which hand costs what is how you stop the bleeding.

The penalty: 1% plus 0.25% per month

The CRA's failure-to-file penalty for a late GST/HST return is calculated under section 280.1 of the Excise Tax Act as a two-part formula:

A + (B × C), where:

• A = 1% of the amount owing on the return
• B = 25% of A (i.e. 0.25% of the amount owing)
• C = the number of complete months the return is overdue, to a maximum of 12

The monthly part is capped: at 12 months the penalty tops out at 4% of the amount owing (1% + 0.25% × 12). Three things matter in practice:

1. Complete months. A return two weeks late counts as zero complete months — the penalty is just the 1% base. A return two months and two weeks late counts as two months. Fixing a missed return this week instead of next month always saves the monthly slice.
2. The amount owing, not the return. A $0 balance or a refund position carries no late-filing penalty. The return is still legally required, but the money penalty is zero.
3. One penalty per late return. Each reporting period's return gets its own penalty if late. Two missed quarterly returns = two penalties.

What it actually costs: worked examples

At the CRA's Q4 2026 prescribed rate of 7% per year, compounded daily, on the unpaid balance:

• $2,000 owing, 3 full months late. Penalty: 1% of $2,000 ($20) plus 0.25% × $2,000 ($5) × 3 months = $35. Interest on $2,000 for ~92 days at 7% compounded daily ≈ $36. Total: about $71.
• $50,000 owing, 6 full months late. Penalty: $500 plus $125 × 6 = $1,250. Interest on $50,000 for ~183 days ≈ $1,786. Total: about $3,036.

The pattern: the penalty is small and linear, but interest is the quiet accumulator — it runs from the payment due date onward, whether or not the return has been filed, and it compounds every day. On large balances, interest overtakes the penalty within months.

Interest starts at the payment due date — not the filing date

For monthly and quarterly filers, return and payment share one deadline (one month after the period ends), so this distinction rarely bites. For annual filers it does: an individual with business income and a December 31 year-end files by June 15 but must pay by April 30. Interest starts on any unpaid balance May 1 — filing "on time" on June 10 does not stop six weeks of interest.

The same applies to instalments: annual filers whose net tax was $3,000 or more in both the previous fiscal year and the current one pay quarterly instalments, due within one month after each fiscal quarter end. Late or insufficient instalments accrue interest at the same daily-compounded prescribed rate.

The prescribed rate is set quarterly by the CRA. For October 1 to December 31, 2026 it is 7% per year on overdue amounts — and it compounds daily under section 124 of the Excise Tax Act, so the effective annual cost runs slightly above the stated rate.

If you owe nothing: the nil and refund positions

• Nil return ($0 owing). No penalty for filing late. But the return is still required — a registrant files for every period, even a nil one. Skipping it creates a gap the CRA will chase with a demand to file.
• Refund position. No penalty, but the late return delays your own money. If you consistently claim refunds, filing late means lending the CRA an interest-free loan while your ITCs sit unprocessed.

Either way: a late refund return delays your money, and repeated gaps erode the compliance record the CRA consults when you ask for anything later.

If the CRA demands you file: the $250 penalty

If the CRA issues a formal demand to file and you do not file, a $250 penalty applies — on top of the late-filing penalty and interest, and even if you owe nothing. This is the trap for nil filers: no balance means no late-filing penalty, but an ignored demand still costs $250.

Two related penalties worth knowing so you do not stack them:

• Paper filing when e-filing is required. For reporting periods ending in 2024 and later, almost all registrants must file electronically. A paper return draws $100 the first time and $250 per return after that.
• Inaccurate reporting on an electronic return. Under- or over-reporting, false statements, or omitting required information can draw a penalty of at least 5% and up to 10% of the incorrect amount.

And one line the CRA states plainly: you cannot claim an income tax deduction for any penalty paid for failing to file a GST/HST return.

How to stop the damage: the recovery sequence

1. File now, pay what you can. The deadline that bites is the filing deadline. An on-time return with an unpaid balance skips the penalty entirely — only interest runs. The same logic applies late: every day you wait, the interest meter runs; every full month, the penalty meter ticks. File the missed return today even if the payment follows next week.
2. File each missed period separately. Multiple missed quarters means multiple returns — file one per period. Do not try to roll a missed period into the current return.
3. Arrange the payment. If you cannot pay in full, the CRA can set up a payment arrangement. Interest keeps running on the unpaid balance, but an arrangement stops collection action and keeps the account in good standing.
4. Ask for relief if the cause was extraordinary. The CRA's taxpayer relief provisions allow cancellation or waiver of penalties — and in some cases interest — in extraordinary circumstances (natural disaster, serious illness, CRA error or delay). The request must relate to a period ending within the 10 calendar years before the year you apply. Relief is discretionary and never guaranteed.
5. Consider voluntary disclosure. Under the current Voluntary Disclosures Program, coming forward on your own — before any CRA communication about the issue — counts as unprompted and can bring 100% penalty relief and 75% interest relief. If the CRA has already written to you about the missed returns, including a demand to file, a disclosure is prompted rather than closed: it can still bring up to 100% penalty relief and 25% interest relief. What ends eligibility is an audit or investigation into the information you would disclose that has already been started — by the CRA or another authority.

Quebec: QST is a separate regime

In Quebec, Revenu Québec administers QST alongside GST/HST, and late-filing consequences for QST follow Revenu Québec's own penalty and interest regime — not the CRA's formula above. Under Quebec's Tax Administration Act, a late QST return draws a penalty of $25 for each day the failure continues, to a maximum of $2,500, and a late payment draws 7% of the amount for the first seven days, 11% for days 8 to 14, and 15% from day 15, plus interest at the rate set by regulation (Revenu Québec guide FPZ-2034.G-V, section 1.1). If you file both, handle the QST side with Revenu Québec's own rules; a CRA demand to file covers the GST/HST return only.

The mistakes that turn a small penalty into a big one

Waiting for the cash before filing. The penalty meter is on the return, the interest meter is on the balance. Filing today and paying next week costs only interest; waiting for the cash costs both.

Treating "I owe nothing" as "I can skip it." Nil returns are required. Skip enough of them and the CRA issues demands — and a $250 demand penalty on a nil return is the most expensive free money you never owed.

Confusing the weekend roll with an extension. When a due date lands on a weekend or holiday, the CRA treats payment as on time if it arrives the next business day. That is breathing room for a bank transfer to clear, not an extra week.

Letting a pattern form. One late return is a fixable error with a calculable cost. A pattern of late returns draws demands, compliance flags, and closer scrutiny of your input tax credits — the consequential costs dwarf the penalty.

Related guides

• How to File a GST/HST Return in Canada, the companion walkthrough: GST/HST NETFILE step-by-step, the 4-digit access code, exact filing deadlines by frequency, and the October 31 quarterly deadline.
• How to Register for GST/HST in Canada, the gate in front of this page: the three registration routes, the Quebec exception, and what to do if you already charged before registering.
• How to Charge GST/HST in Canada, the step before filing: which rate to charge by customer province, the place-of-supply rules, and how to invoice the tax.
• How to Look Up a GST/HST Number in Canada, verify a supplier's number before you claim ITCs against their invoices.

Sources

• Canada Revenue Agency, GST/HST penalties and interest — the failure-to-file formula, the $250 demand penalty, the electronic-filing penalties, and the rule that a filing penalty cannot be deducted
• Canada Revenue Agency, RC4022 General information for GST/HST registrants — filing and payment due dates, the June 15 / April 30 split for annual filers, the instalment test, and the next-business-day rule
• Canada Revenue Agency, Prescribed interest rates, October 1 to December 31, 2026 — the 7% overdue rate used in the worked examples
• Canada Revenue Agency, GST/HST Memorandum 16.3, Cancellation or Waiver of Penalties and Interest — the taxpayer relief circumstances and the 10-calendar-year limit
• Canada Revenue Agency, GST/HST Memorandum 16.5-1, Voluntary Disclosures Program — the current unprompted and prompted relief tiers, and the audit-or-investigation bar on voluntariness
• Revenu Québec, Guide to Detailed GST/HST and QST Calculations (FPZ-2034.G-V, 2026-09) — section 1.1 sets out the QST late-filing and late-payment penalties under Quebec's Tax Administration Act