The federal corporate year-end deadline
If you operate through a corporation, your first obligation is to file the corporate tax return within six months of your fiscal year-end. This is a firm deadline. The CRA will assess a penalty equal to the greater of $100 or 25 percent of any unpaid tax owed, and interest accrues daily on anything outstanding.
Before that corporate return goes to the CRA, you typically need to have your year-end financial statements prepared. Most owner-operated businesses file on a calendar-year basis, making December 31 the cutoff, which means the corporate return is due by June 30. If your business runs on a different fiscal year, your deadline is six months after that year-end closes.
Personal tax return and installment payments
As a business owner, you file a personal return by June 15, though payment is due by April 30. This matters because the CRA charges interest on late payments even if your return itself is filed on time.
If you’re self-employed or the corporation paid you a dividend, you may also owe quarterly installment payments. These are required when your tax liability exceeds a threshold (typically around $3,000). Missing an installment triggers a penalty of 1 percent of the shortfall, plus daily interest.
GST and PST deadlines vary by revenue
Sales tax obligations depend on whether you’re registered and your filing frequency. If you file monthly, your GST return is due the last day of the following month. Quarterly filers have 30 days after the quarter ends. Late filing brings penalties starting at $100 per month.
PST deadlines in British Columbia follow a similar structure, though timing and thresholds differ slightly from GST. Many businesses file both simultaneously.
Payroll remittance deadlines
If you have employees, payroll deductions must be remitted to the CRA by the 15th of the following month. The sooner you remit, the sooner you recover cash flow, but the deadline is non-negotiable. Penalties on late payroll remittance are particularly steep, starting at 10 percent of the amount owing.
What happens when you miss a deadline
Penalties compound quickly. A missed quarterly GST filing triggers a $100 penalty immediately. If you miss the next one, that rises to $200. Three or more misses in a row put you in a different penalty category altogether.
More importantly, the CRA begins enforcement. They may file a winding-up assessment, freeze your GST input tax credits, or pursue director liability if the corporation owes payroll remittances.
Setting a calendar reminder on April 15 and June 15 catches the main deadlines, but your accountant should flag installments, GST quarters, and any custom dates based on your specific year-end. We track all of these for our clients and issue reminders before each due date.
This article is general information, not financial advice, and it may not reflect the latest rules or your own situation. Talk to Ledgerline Accounting about your circumstances before acting on it.