What’s the HST filing deadline for a quarterly filer in Ontario Q3 2026?
For a quarterly HST filer, Q3 2026 (July 1 to September 30, 2026) is due on Monday, November 2, 2026, because October 31 falls on a Saturday. Both the return (GST34) and the net-tax payment must reach CRA by that date.
Excise Tax Act s. 238(1) requires a quarterly registrant to file the GST34 return within one month after the end of each reporting period. Section 245 imposes payment on the same date. When the statutory deadline lands on a weekend or federal holiday, s. 26 of the Interpretation Act rolls it to the next business day, so a return owing $8,000 net HST for Q3 2026 must clear CRA by end of day Monday, November 2, 2026.
Late-filing penalty under s. 280.1 is: A (1% of unpaid amount) plus B (25% of A times each complete month up to 12). Arrears interest under s. 280 accrues daily at the prescribed rate. A $10,000 balance filed three months late costs $175 in s. 280.1 penalty alone, before interest.
Note: Filing frequency is set annually based on threshold sales; a business with annual taxable sales above $1.5 million cannot use annual reporting and defaults at least to quarterly (ETA s. 248).
Source: canada.ca â GST/HST reporting periods
— Bader A. Chowdry, CPA, CA, LPA — Insight Accounting CPA
Disclaimer: Bader A. Chowdry, CPA, CA, LPA is a Licensed Public Accountant regulated by CPA Ontario. Insight Accounting CPA Professional Corporation is a Chartered Professional Accountant firm. This content is general information only and does not constitute professional advice for your specific facts. Confirm current rules and figures with your own advisor before acting.