Ontario Tax Deadlines Every Small Business Owner Should Know

If there's one thing the Canada Revenue Agency (CRA) is uncompromising about, it's deadlines. The good news is that the calendar is predictable — once you know which dates apply to your business, you can plan around them instead of scrambling to meet them. Here's a practical rundown of the deadlines that matter most for Ontario businesses.

Personal (T1) tax deadlines

For most individuals, the T1 filing deadline is April 30. If you or your spouse are self-employed, the filing deadline extends to June 15 — but any balance owing is still due April 30. This distinction trips up a lot of sole proprietors: you get more time to file, but not more time to pay.

Corporate (T2) tax deadlines

A T2 corporate return is due six months after your fiscal year-end. However, any tax owing is due two months after year-end — or three months after year-end if you meet the small business criteria and your balance is under a certain threshold. Get the year-end right, and the rest of the calendar follows from it.

Recurring remittance deadlines

• HST/GST returns: due based on your reporting period (monthly, quarterly, or annually).
• Source deductions (CPP, EI, income tax): remitted by the 15th of the following month (or sooner for larger payrolls).
• T4 and T4 summaries: due by the last day of February each year.
• WSIB premiums: reported and paid monthly or quarterly depending on your account.

The simplest way to never miss one is to let someone track them for you. Our full-cycle bookkeeping service manages every remittance on a fixed schedule — so deadlines become routine instead of an emergency.