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Form 1120 is not a Canadian form. It’s the U.S. Corporation Income Tax Return, filed with the IRS by domestic U.S. corporations, and a calendar year company sends it in by April 15. A Canadian corporation files a T2 with the CRA instead.
Who files Form 1120?
The IRS says domestic corporations file it to report income, gains, losses, deductions and credits, and to work out their tax. “Domestic” means a company set up in the United States. If you run a Canadian business, you’re probably looking at the wrong form, unless you own a U.S. company.
A Canadian corporation doing business in the United States isn’t automatically in the same spot. The IRS uses a different return, Form 1120-F, for foreign corporations. If you have to file that one, and what it covers, depends on how you operate in the U.S., and we haven’t researched it here. A cross-border accountant can answer that in one meeting.
How does it compare with the Canadian T2?
| Item | U.S. Form 1120 | Canadian T2 |
|---|---|---|
| Who files | U.S. domestic corporations | Corporations resident in Canada |
| Filed with | IRS | CRA |
| Filing date | 15th day of the 4th month after year end | Six months after year end |
| Extension | Form 7004 | Not confirmed for this page |
| Balance owing | Not confirmed for this page | Two months after year end, three for a qualifying CCPC |
For a December 31 year end, the 1120 is due April 15 and the T2 on June 30. The U.S. date comes first, which catches Canadians who assume both run on the Canadian calendar.
There’s one more difference to keep straight on the Canadian side. The T2 filing date and the date you have to pay are not the same day. The CRA’s page on corporate payment due dates sets the general balance-due day at two months after year end, with three months for a CCPC that meets its tests. For a December 31 year end that means the money is due at the end of February, or the end of March for a qualifying CCPC, months before the return itself.
What if my Canadian company owns a U.S. company?
Then two returns are in play. The U.S. company files Form 1120 in the U.S. Your Canadian company files its own T2, and the CRA expects you to report the foreign company on Form T1134 as a foreign affiliate, which is due 10 months after your year end for recent years. Profit taxed in the U.S. isn’t automatically ignored in Canada, and how the two systems fit together is where an adviser earns the fee.
To get a feel for the Canadian side, use the corporate tax calculator. On $300,000 of active business income for a small CCPC, it shows $27,000 of federal tax, the 9% small business rate, and then adds your province. It doesn’t handle foreign income or credits for U.S. tax, and we didn’t confirm U.S. rates for this page, so we don’t compare the two.
What does this look like for a real owner?
Take Raj in Mississauga, who runs a Canadian software company and sets up a small Delaware company to sell to American customers. He now has a Canadian year end and a U.S. one to think about, plus a T1134 on the Canadian side. His first mistake would be to put the U.S. filing on the same reminder as his T2. His second would be to wait for his Canadian bookkeeper to mention it.
The fix costs a few bucks and an hour. Put both returns on one calendar, with the earlier U.S. date first, and ask a cross-border adviser to check the setup once before the first filing season.
What do you need before filing either return?
The same base material, really. An income statement, a balance sheet, a list of expenses with receipts, and a clear picture of what was paid to owners. If you pay yourself in dividends, work through the dividend tax calculator so you know what lands on your personal return. The profit margin calculator is a quick check on your books before an accountant sees them.
Mistakes that cost time
Searching for “Form 1120” and filling in the first PDF you find is the classic one. Check the country, the tax year and whether the entity is domestic.
Next, using the Canadian year end for the U.S. company. Each country works from its own filing calendar.
Last, forgetting the paper trail. The CRA wants business records for six years from the end of the last tax year they relate to, and the U.S. company will have its own retention needs. We didn’t check the IRS side.
If the U.S. company is new, start the file when you form it, not when the first deadline is close.
Sources, and how we checked them
Form 1120 details come from the IRS page about the form. The T2 dates, T1134 timing, record keeping and the federal corporate rates come from Canada Revenue Agency pages and its T2 guide, all read in November 2026. The IRS Form 1120 page was last reviewed August 19, 2026. This site has no connection with the IRS, the CRA or any government. The CRA corporate payment dates page (page-details date January 21, 2026), the T1134 page and the corporation tax rates page were read in November 2026. All official pages were checked in November 2026.
Frequently asked questions
Is Form 1120 a Canadian form?
No. Form 1120 is the US Corporation Income Tax Return, filed with the IRS by domestic US corporations to report income, gains, losses, deductions and credits. A Canadian corporation files a T2 return with the CRA instead. If you own a US company as well, you may deal with both returns.
When is Form 1120 due compared with the Canadian T2?
For a calendar year corporation, Form 1120 is due April 15 and the T2 is due six months after year end, which is June 30 for a December 31 year end. The US date comes first. The T2 balance owing is due earlier than the T2 filing date.
When is the balance owing due on a Canadian corporate return?
The CRA says most corporate tax is due two months after the end of the tax year. A CCPC can get three months if it was a CCPC throughout the year, claimed the small business deduction in the current or previous year, and its prior-year taxable income was within its business limit.
What if my Canadian company owns a US company?
Two returns are in play. The US company files Form 1120 in the US, and your Canadian company files its own T2. The CRA also expects Form T1134 for a foreign affiliate, due 10 months after year end for tax years beginning after 2020. A cross-border adviser can set this up.
Does a Canadian corporation file Form 1120-F?
It depends on how it operates in the US. The IRS uses Form 1120-F for foreign corporations that have US income or a US business, and whether you must file it depends on your activity there. We have not researched that return here, so ask a cross-border accountant before the first filing season.
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