1. Which HST deadline is actually yours
Your HST due date starts with your reporting period (the chunk of time your HST return covers — monthly, quarterly, or annual, set when CRA assigned your filing frequency). CRA does not give everyone the same calendar.
Monthly and quarterly filers are usually on a one-month lag. But annual filers can have a three-month filing rule, a split filing and payment rule, or instalments layered on top.
This is why owners should confirm filing frequency first, not last. Our GST/HST guide and our HST filing frequency guide are the right starting points if you are not fully sure how CRA set you up.
2. Monthly filer calendar for 2026
CRA's rule is simple here: the return and the payment are due 1 month after the end of the reporting period. So the only real work is checking which dates land on weekends.
- January 2026 period → February 28, 2026, treated as on time on Monday, March 2, 2026
- February 2026 period → March 31, 2026
- March 2026 period → April 30, 2026
- April 2026 period → May 31, 2026, treated as on time on Monday, June 1, 2026
- May 2026 period → June 30, 2026
- June 2026 period → July 31, 2026
- July 2026 period → August 31, 2026
- August 2026 period → September 30, 2026
- September 2026 period → October 31, 2026, treated as on time on Monday, November 2, 2026
- October 2026 period → November 30, 2026
- November 2026 period → December 31, 2026
- December 2026 period → January 31, 2027, treated as on time on Monday, February 1, 2027
monthly filers miss HST when they trust memory instead of a calendar. So if monthly is your frequency, build these dates into the same workflow as payroll and bank reconciliations.
3. Quarterly filer calendar for 2026
Quarterly HST is the same rule with fewer returns. And for most Ontario businesses, that is easier to manage as long as the cash is still being set aside every month.
- Q1 2026, January 1 to March 31 → April 30, 2026
- Q2 2026, April 1 to June 30 → July 31, 2026
- Q3 2026, July 1 to September 30 → October 31, 2026, treated as on time on Monday, November 2, 2026
- Q4 2026, October 1 to December 31 → January 31, 2027, treated as on time on Monday, February 1, 2027
Quarterly filing is where owners get overconfident. Our full 2026 deadline calendar is useful here because HST is rarely the only date you are carrying.
4. Annual filer rules and split dates
Annual HST is where the clean one-line rule disappears. For a non-individual annual filer, the return and payment are generally due 3 months after fiscal year-end.
So a December 31, 2026 corporate-style year-end points to March 31, 2027. But a December 31, 2026 individual annual filer with business income usually files by June 15, 2027 while any balance owing is due April 30, 2027.
The thing is, that June 15 and April 30 split catches people every year. Sole props should treat April 30 as the real deadline and June 15 as paperwork cleanup time only.
5. Instalment dates for annual filers
Some annual filers have to pay during the year, not just at the end. An instalment (a quarterly prepayment annual filers make toward their next HST balance, due before the actual return) is generally required when prior-year net tax hits the $3,000 threshold.
CRA says the instalment is due within 1 month after each fiscal quarter ends. So a calendar-year annual filer is looking at April 30, 2026, July 31, 2026, October 31, 2026, treated as on time on Monday, November 2, 2026, and January 31, 2027, treated as on time on Monday, February 1, 2027.
instalments are where annual filers get lulled into a false sense of safety. We've found that one missed instalment can turn an otherwise tidy annual return into an interest story.
6. Weekend and holiday shifts
CRA's rule is generous on weekends and recognized public holidays. If a due date lands on a Saturday, Sunday, or a public holiday recognized by CRA, your return or payment is on time when CRA receives it on the next business day.
For Ontario businesses in the 2026 HST cycle, the CRA holiday dates worth watching are January 1, 2026, April 3, 2026, April 6, 2026, May 18, 2026, July 1, 2026, August 3, 2026, September 7, 2026, October 12, 2026, November 11, 2026, December 25, 2026, and December 26, 2026. So Boxing Day on Saturday, December 26, 2026 pushes the next business-day effect to Monday, December 28, 2026.
this is where a saved recurring calendar wins. Our GST/HST mistakes and penalties guide pairs well with this section because late HST problems usually start with one missed date.
7. Late penalties and interest
CRA's standard late-filing penalty is 1% of the amount owing, plus 0.25% of that amount for each complete month the return is late, to a maximum of 12 months. But that is only the filing penalty piece.
CRA also charges interest on overdue HST balances at the prescribed rate (the interest rate CRA uses for tax debts, set every three months — published on canada.ca). And because the rate is reset every 3 months, a stale rule of thumb is not good enough.
Late HST should be treated as urgent on day 1, not day 30. If you want the filing calendar and the money movement handled together, our HST filing service is the cleanest next step.
HST deadlines are easy to understand once, and easy to forget later. If you want the 2026 dates and filings handled properly, we can help.
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