Here are the 2026 CRA deadlines that matter most for Ontario businesses: RRSP contributions and T4/T5 slips are due March 2, 2026; personal tax is due April 30, 2026 (self-employed owners get until June 15 to file, but any balance owing is still due April 30); and corporate returns are due six months after your fiscal year-end. HST deadlines depend on how often you file. The full calendar is below.
Keep this page bookmarked — when a deadline falls on a weekend or public holiday, the CRA moves it to the next business day. Miss one when you owe money and penalties plus daily interest start adding up, so knowing your dates in advance is the whole game.
Key 2026 dates at a glance
- March 2, 2026 — RRSP contribution deadline (for the 2025 tax year) and T4/T5 slips filed with the CRA and given to employees.
- April 30, 2026 — Personal income tax (T1) filing and payment deadline — including balances owing for self-employed owners.
- June 15, 2026 — T1 filing deadline for self-employed individuals and their spouses (payment was still due April 30).
- Six months after year-end — Corporate tax return (T2) filing.
- Two months after year-end — Corporate tax payment (three months for a CCPC claiming the small business deduction).
- 15th of each month — Payroll source deductions for most employers.
- HST — Depends on your filing frequency (see below).
Personal income tax deadlines (T1)
For the 2025 tax year, individuals in Ontario must file their T1 return and pay any balance owing by April 30, 2026. If you or your spouse are self-employed, you have until June 15, 2026 to file — but this is the trap that catches people every year: your payment is still due April 30. So even self-employed owners should have their numbers ready by the end of April to avoid interest on a balance owing.
RRSP contributions and T4 slips: March 2, 2026
Two important dates land at the start of March. The deadline to contribute to your RRSP and have it count against your 2025 income is March 2, 2026 (the usual March 1 date falls on a Sunday this year). And if you run payroll, your T4 and T5 slips must be filed with the CRA and provided to employees by March 2, 2026 as well. Late slips carry their own penalties, so this is a date every Ontario employer should have circled.
Corporate tax (T2) deadlines depend on your year-end
Unlike personal tax, corporate deadlines are tied to your company's fiscal year-end, not the calendar. Your T2 return is due six months after your year-end, and your tax payment is due two months after year-end — extended to three months for a Canadian-controlled private corporation (CCPC) claiming the small business deduction. For example, a December 31, 2025 year-end means payment by the end of February or March 2026 and filing by June 30, 2026. Keeping your books current all year is what makes hitting these dates painless.
HST/GST deadlines: it depends on your filing frequency
The CRA assigns your HST reporting period based on your revenue, and each frequency has its own deadline:
- Annual filers with a December 31 year-end and business income: file by June 15, 2026, but pay any balance by April 30, 2026.
- Quarterly filers: file and pay one month after each quarter — for calendar quarters that's April 30, July 31 and October 31, 2026, then January 31, 2027.
- Monthly filers: file and pay one month after the end of each month.
If you're an annual filer and your net HST last year was $3,000 or more, the CRA also expects quarterly instalments during 2026 — due March 31, June 30, September 30 and December 31 — with everything reconciled on your annual return. Not sure which schedule you're on? See our plain-language guide to HST in Ontario, or we'll confirm it for you.
Payroll remittances and tax instalments
If you have employees, source deductions (CPP, EI and income tax) for most Ontario businesses are due by the 15th of the month after you paid your staff — so wages paid in January are remitted by February 15, 2026. Personal and corporate tax instalments, where required, are generally due quarterly on the 15th of March, June, September and December. Missing payroll remittances is one of the fastest ways to draw CRA penalties, so these dates deserve a permanent spot in your calendar.
What happens if you miss a deadline?
When you owe money and file late, the CRA charges a penalty of 1% of the balance owing, plus 0.25% for each full month you're late, up to 12 months, and daily compound interest runs on any unpaid amount from the day after the due date. The good news: filing on time avoids the late-filing penalty entirely, even if you can't pay the full balance right away. That's why we keep our clients' books reconciled year-round and their filing dates in the calendar — so tax season is a non-event. Take a look at our monthly bookkeeping or tax filing service.
Frequently asked questions
When is the tax filing deadline for a small business in Ontario in 2026?
It depends on your structure. Sole proprietors and self-employed owners file their T1 by June 15, 2026, but must pay any balance by April 30, 2026. Incorporated businesses file their T2 six months after their fiscal year-end and pay two to three months after year-end. HST follows its own schedule.
How much is the CRA penalty for filing late?
If you owe money, the late-filing penalty is 1% of the balance plus 0.25% for each full month you're late, up to 12 months, plus daily compound interest on the unpaid amount. Filing on time avoids the penalty entirely — even if you can't pay in full yet — so always file by the deadline.
What happens if I miss my HST filing deadline?
The same penalty formula applies: 1% of the balance owing plus 0.25% per full month late, up to 12 months, with interest running daily. You must also file even in periods where you owe nothing. Staying reconciled monthly makes HST filing a quick, stress-free job instead of a scramble.
Never miss a CRA deadline again.
We keep your books reconciled and your filings on time — across Ottawa and all of Ontario. Book a free 15-minute call and we'll map out your dates.
Book a Free Consultation →This article is general information, not tax advice. Deadlines that fall on a weekend or holiday move to the next business day, and your exact dates depend on your fiscal year-end and CRA-assigned filing frequency — always confirm your own.