SR&ED Claim Deadline Calculator
Missed SR&ED last year? You may still be in time. Enter your fiscal year end to see which tax years you can still claim, and the CRA cut-off date for each.
Your fiscal year end
Calculating deadlines…
For corporations, using the CRA’s month-counting rule. It assumes the same year end every year. If you changed your year end or had a short first year, enter each year end separately. Public holidays are not checked. This is general information, not tax advice.
How the 18-month rule works
For a corporation, the SR&ED reporting deadline is 12 months after the T2 return is due. The T2 is due 6 months after the tax year end, so the deadline is 18 months after the year end. By then you must have filed Form T661 and Schedule T2SCH31, with the project descriptions and expenditures, for that year.
The CRA counts in months, not days. A year end on the last day of a month moves to the last day of the month. A year end on any other day keeps that day: a January 6 year end gives a July 6 deadline the following year.
The deadline is firm. The CRA cannot give extra time, and after the deadline it cannot accept a claim or changes to one. The only allowance is for weekends and CRA public holidays: then the claim is on time if it arrives, or is postmarked, by the next business day.
Different rules apply to individuals (17½ months after the calendar year end), trusts (generally 15 months) and non-profit SR&ED corporations (6 months). This calculator covers corporations only.
Source: CRA SR&ED Filing Requirements Policy (January 28, 2025), sections 5.2, 5.3, 6.2 and questions 5 to 8.
Who usually finds out late
Software and AI teams
Many startups hear about SR&ED after they have filed their first T2. If you worked through technical problems with no known answer, like scaling, model performance or a hard integration, that year may still be open. You can ask the CRA to reassess the filed return and add the claim before the deadline.
Manufacturers and machine builders
Custom equipment, automation and process work often contain eligible experimentation that nobody wrote up as R&D at the time. The same 18-month window applies, so a year you thought was closed may not be.
Whether you are in time is the first question. The second is whether the work qualifies and whether you can describe it the way Form T661 asks. The deadline covers the project descriptions as well as the numbers, so leave time to write them.
Frequently Asked Questions
What is the SR&ED filing deadline for a corporation?
The SR&ED reporting deadline is 12 months after your T2 return is due, and the T2 is due 6 months after your tax year end. For corporations that is 18 months after the tax year end. A December 31, 2025 year end has a deadline of June 30, 2027.
Is the 18 months counted in days or months?
Months. If your tax year ends on the last day of a month, the deadline is the last day of the month 18 months later. If it ends on another day, the deadline is that same day 18 months later. The CRA's own examples: a February 28 year end gives an August 31 deadline the following year, and a January 6 year end gives July 6 of the following year.
Can the CRA extend the SR&ED deadline?
No. The CRA cannot allow extra time beyond the SR&ED reporting deadline, and it cannot accept a claim, or changes to one, after it. If the deadline falls on a Saturday, Sunday or CRA public holiday, the claim is on time if the CRA receives it, or it is postmarked, by the next business day.
I already filed my T2 without SR&ED. Can I still claim?
Yes, if the SR&ED reporting deadline for that year has not passed. You ask the CRA to reassess the return and include the SR&ED claim, filing Form T661 and Schedule T2SCH31 by the deadline.
Why file 90 days before the deadline?
The CRA says that a claim filed at least 90 days before the reporting deadline gives it time for an initial review and to tell you if anything is missing. If you file closer to the deadline and something is missing, you may not be able to fix it in time, and those expenditures are lost.
What happens if part of my claim is late or incomplete?
The CRA does not reject the whole claim. It cannot accept missing information after the deadline, though, so any project whose details were not filed on time loses its expenditures. In the CRA's example, a claimant filed project details for 10 of 15 projects. The costs for the other 5 were not allowed.
Have an open year? Check it before the window closes.
In a free 20-minute call we look at what you built in the open years, whether it likely qualifies, and what you need to file before each deadline.
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