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A company tax return, the T2, is due six months after your corporation’s tax year ends. The tax itself is usually due much sooner, two months after year end, or three for many small Canadian-controlled private corporations. So the return can wait, but the money can’t.
When is the company tax return due?
Count six months from the last day of the tax year. A year ending March 31 gives you September 30, and a year ending August 31 gives you February 28. If the year ends mid month, use the same calendar day six months later. A deadline on a weekend or CRA holiday moves to the next business day.
| Tax year ends | T2 return due |
|---|---|
| March 31 | September 30 |
| August 31 | February 28 |
| September 23 | March 23 |
| October 2 | April 2 |
Your tax year doesn’t have to match the calendar. Many corporations use a December 31 year end, but yours is whatever you set when you incorporated. And a dormant company still has a job to do: the CRA’s corporation income tax return page says resident corporations file a T2 every year even if no tax is payable.
When do you have to pay?
This is where owners get burned. The general rule is two months after the year ends. The three month rule applies only if the corporation was a CCPC all year, claimed the small business deduction this year or last, and had prior year taxable income within its business limit (with associated corporations sharing that limit). Miss one condition and the two month date applies.
Take Mia’s company, with a March 31 year end. The return is due September 30. The tax is due May 31 under the two month rule, or June 30 if the three month rule applies. So she has four months of breathing room on the paperwork, but the cash has to be ready long before.
Corporations that owe tax may also have to pay instalments during the year. We didn’t confirm the instalment rules for this page, so read the CRA’s instalment dates page before you rely on a schedule.
How much company tax will we owe?
Federal rates are 15% for general income and 9% on the first $500,000 of qualifying small business income. Provinces add their own. Our corporate tax engine gives these Ontario results for a CCPC using the small business rate.
| Taxable income | Federal | Ontario | Total |
|---|---|---|---|
| $100,000 | $9,000 | $2,696 | $11,696 |
| $250,000 | $22,500 | $6,740 | $29,240 |
| $600,000 | $60,000 | $24,980 | $84,980 |
Treat the Ontario column with care. The small business rate is being cut from 3.2% to 2.2% from July 1, 2026, and the calculator blends the two for a calendar 2026 year. That blend is our own arithmetic, not a published figure, and a corporation with a different year end will get a different result. At $600,000 the engine also takes the general rate on the amount over $500,000, and it ignores the passive income and taxable capital reductions.
Not a CCPC, or no small business deduction? The same $100,000 comes to $26,500 at the general rate of 26.5%. Try your own figures in the corporate tax calculator.
What else has to line up before you file?
The corporation’s return and your own are separate filings. If you pay yourself salary, remittances have their own schedule, which the payroll remittance calculator can help with. If you take dividends instead, the dividend tax calculator shows what you’d owe personally.
Gather the financial statements, a list of shareholders and any notes on loans between you and the company before you start. The CRA keeps a page of software for filing corporation returns online. Who does the filing, you or an accountant, matters less than whether the books are clean by the due date.
What does a sensible calendar look like?
Work backwards from the earlier date. A few weeks after year end, close the books. Before the payment date, estimate the tax and move the cash. Only then worry about the T2 itself, which has months to spare. It’s the same logic as saving for a rainy day: the cheque to the taxman is the part with a short fuse, and the paperwork is the part you can polish.
Which mistakes should you avoid?
Confusing the filing deadline with the payment deadline is number one. Number two is assuming the small business rate applies without checking the conditions. And a third, quieter one: forgetting associated corporations share the $500,000 limit, so two companies under common control don’t each get the full amount.
Late filing brings penalties and interest. We haven’t confirmed the current penalty rates for this page, so read the CRA’s page before you guess at the cost.
Sources, and how we checked them
Filing and balance due rules come from the CRA‘s pages on when to file a corporation return and on balance-due day. Federal rates come from the CRA corporation tax rates page and the T2 guide. Ontario figures come from the CRA’s Ontario corporation page and its what’s new notice. We aren’t a government service and we don’t speak for one.
Frequently asked questions
When is a company tax return due in Canada?
Six months after the end of the corporation's tax year. A March 31 year end means September 30.
When do I pay corporate tax?
Usually two months after the year ends. Some CCPCs that claimed the small business deduction get three months.
What is the federal small business rate?
The CRA shows 9% on the first $500,000 of qualifying income. The general rate is 15%.
Does a small corporation pay less tax in Ontario?
Yes, the small business rate is lower. Our engine gives $11,696 in combined tax on $100,000, but the 2026 provincial rate is changing mid year.
What if the deadline falls on a weekend?
Your return is on time if the CRA receives it or it's postmarked by the next business day.
- How to file your tax return in Canada: steps and dates
What to gather, when your return is due and how to file in Canada, from the first slip to the notice of assessment that closes the year