Every corporation in Canada must file its T2 income tax return within six months of the end of its tax year. For the large number of Toronto-area corporations that use a December 31 fiscal year-end, that made June 30, 2025 the T2 filing deadline for the 2024 tax year. The rule itself is not new — it's a standing CRA requirement, not an announced change — but it's worth restating precisely each year because the six-month window and the payment deadline inside it are easy to get slightly wrong, and getting them wrong is what generates late-filing penalties on an otherwise well-run corporation.
Source: Government of Canada — When to file your corporation income tax return.
The six-month rule, precisely
The CRA's rule has two forms depending on whether the tax year ends on the last day of a month:
- If the tax year ends on the last day of a month, the T2 is due on the last day of the sixth month after that.
- If the tax year does not end on the last day of a month, the T2 is due on the same calendar day of the sixth month after that.
For a December 31 year-end, six months later is June 30 — the last day of June, matching the "last day of a month" rule cleanly. For an off-calendar year-end, the same-day rule applies instead: a March 15 year-end has a September 15 filing deadline, for example. When the calculated due date lands on a Saturday, Sunday, or public holiday, the CRA treats the return as on time if filed the next business day.
Filing deadline vs. payment deadline — the split that trips up CCPCs
As with the personal T1, the corporate filing deadline is not the same as the payment deadline. The CRA calls the payment date a corporation's "balance-due day," and for most corporations it falls well before the six-month filing deadline — the return itself reports and reconciles instalments already paid, rather than triggering the tax bill on its own. A corporation should never assume that a June 30 filing deadline means the associated tax is also due on June 30; the two are governed by separate rules, and the balance-due day for a given corporation depends on its size, its eligibility for the small business deduction, and whether it is associated with other corporations.
Source: Government of Canada — Balance due when filing a corporate income tax return.
This is the detail most likely to catch a Toronto business owner off guard: a corporation can file its T2 perfectly on time by June 30 and still owe CRA arrears interest on an unpaid balance, because the balance-due day fell earlier in the year, well before the return itself was even close to finished. Filing on time and paying on time are two separate obligations with two separate clocks — confirm your corporation's specific balance-due day with your accountant rather than assuming it lines up with the June 30 filing date.
A worked example
| Item | December 31, 2024 year-end |
|---|---|
| Tax year-end | December 31, 2024 |
| T2 filing deadline (6 months later) | June 30, 2025 |
| Balance-due day (falls earlier in the year — depends on the corporation's own eligibility) | Confirm with your accountant; do not assume it matches June 30 |
| Instalment payments through the year | Monthly or quarterly, depending on prior-year tax and eligibility |
The gap between when the tax is actually owed and when the return itself is due is exactly why year-round instalment planning matters more than the June filing date itself — a corporation that has been paying reasonable instalments through 2024 arrives at its balance-due day with little or no surprise balance; one that hasn't can face a large balance-owing payment well before the T2 is even close to finished.
What Toronto-area corporations should do
- Confirm your own year-end before assuming June 30 applies to you. The six-month filing rule is universal, but the specific date depends entirely on your corporation's own fiscal year-end, not the calendar year.
- Separate the filing deadline from the payment deadline in your own planning. For a December year-end, the balance owing was due two or three months before the return, not on the same date.
- Review your instalment schedule against actual 2024 results, not just against last year's instalment base, especially if income grew meaningfully year over year.
- If your corporation is close to the small business deduction limit, the T2 filing season is the natural point to revisit it alongside the return itself — see our small business deduction limit guide.
- Budget payroll costs for the coming year while the T2 numbers are fresh, using a tool like our employer payroll cost calculator rather than carrying forward last year's assumptions unchanged.
The bigger picture
The T2 six-month filing rule doesn't change year to year, which is exactly why it's worth restating precisely rather than assumed from memory — the rule is stable, but the specific dates it produces depend entirely on your own corporation's year-end, and the payment deadline buried inside that six-month window is easy to miss until arrears interest shows up on a statement. For most December year-end corporations, the return itself isn't the risk; the balance-owing deadline that passed months earlier, quietly, is.
If your Toronto corporation's instalments, balance-owing timing, or T2 filing need a second look before the next year-end comes around, RN Canada works with Ontario CCPCs remotely from our Edmonton and Vancouver offices through our tax return preparation services.