By OptiVal Editorial Desk
The most expensive line on some Canadian companies’ books is not a missed grant. It is a research and development tax credit that died on a calendar technicality. The SR&ED claim deadline in Canada is one of the strictest filing dates in the tax system: 18 months after your fiscal year end for a corporation, 17.5 months for an individual, and the CRA grants no extensions. Miss it and the entire claim for that year is gone. There is no late-filing relief, no discretionary waiver, no appeal on lateness.
This matters more than most owners realise, because SR&ED is generous. Most Canadian-controlled private corporations (CCPCs) can claim a 35% refundable investment tax credit on the first $6 million of qualifying R&D spending for tax years starting after December 15, 2024, with 15% above that threshold. A refundable credit is cash, even in a year with no tax payable.
The SR&ED claim deadline, stated plainly
The rule comes from the CRA’s own filing requirements for the program. Your SR&ED reporting deadline is 12 months after the filing due date of your income tax return for the year. Because a corporation’s T2 return is due six months after its fiscal year end, the arithmetic lands at 18 months after year end for corporations and 17.5 months for individuals. The legal references are subsections 37(11), 37(11.1) and 37(12) of the Income Tax Act, and the CRA’s Guide to Form T661 states the consequence in plain terms: if you do not report an expenditure on Form T661 by the SR&ED reporting deadline, you will not be entitled to receive the SR&ED incentives for that expenditure.
Two things about that wording deserve attention. First, the deadline is anchored to the return’s due date, not to when you actually filed. Filing your T2 early does not buy extra SR&ED time, and filing it late does not push the deadline out. Second, the claim is filed per tax year. A project that runs for three years generates three separate claims, and missing the window for year one does not affect year two, but it permanently wipes out year one’s credit.
A worked example: December 31 year end
Take a CCPC whose fiscal year ends December 31, 2026. Its T2 corporate return is due June 30, 2027, six months after year end. The SR&ED reporting deadline is 12 months after that filing due date, which lands on June 30, 2028. Counted from the fiscal year end, that is exactly 18 months.
Miss June 30, 2028, and the entire 2026 SR&ED claim is lost. The company can still claim its 2027 spending (whose deadline is June 30, 2029), but the 2026 work, the salaries, the contractor costs, the materials, can never generate a credit. For a company spending $500,000 a year on eligible R&D, a single missed deadline can cost $175,000 of refundable credit. That is the scale of the mistake.
What counts as “filed”
Filing a SR&ED claim means submitting Form T661, the SR&ED Expenditures Claim, together with the right supporting schedule: Schedule T2SCH31 (Investment Tax Credit, Corporations) for corporations, or Form T2038(IND) for individuals. The CRA says these should be filed with your income tax return for the year. If you are amending the forms and filing electronically, they must be filed with an income tax return for the year.
The CRA recommends submitting the SR&ED claim at the same time as your T2 return. Processing is faster that way, and it removes the biggest behavioural risk: the claim sitting in a “we’ll get to it” pile until month 16. You can file the claim later than the return, any time before the deadline, but the deadline does not care about your intentions.
One special case worth knowing: a corporation that is exempt from tax and incurs SR&ED expenditures must file Form T661 on or before the due date of its return of income for the year (the six-month mark), or it faces a penalty.
What happens if you miss it
Nothing, and that is the problem. There is no late-filing penalty to pay and no way back in. The CRA does not accept late SR&ED claims and does not grant extensions, whatever the reason. An accountant’s oversight, a crashed hard drive, a change of bookkeeper mid-year, none of it restores the claim.
Two things the deadline does not affect. An unused SR&ED investment tax credit can be carried back up to three years or carried forward up to 20 years, but only if the original claim was filed within the deadline. The carry provisions move the credit across years; they do not excuse a late claim. And filing a SR&ED claim in a year when the company owes no tax is not pointless: the refundable portion still comes back as a refund, and the rest can be banked through the carry rules.
The four mistakes that kill claims
Most missed deadlines share a pattern. First, the company starts reconstructing records in month 16 or 17. By then the developers who did the work have forgotten which sprint tackled which technical uncertainty, the time logs are estimates, and the Part 2 project narratives read like product marketing instead of technical descriptions. CRA reviewers reject exactly that framing.
Second, the owner assumes the accountant handles it. Many general-practice accountants do not ask about R&D activity, and SR&ED is a specialist claim. If your accountant has not mentioned it, ask. Third, the company confuses the T2 filing deadline with the SR&ED deadline and assumes filing the return late buys breathing room. It does not, because the window is anchored to the due date. Fourth, the company changes its fiscal year end and nobody recalculates the window. Every tax year gets its own 18-month clock, measured from its own year end.
A timeline that never misses the window
The practical fix is boring. Keep time records contemporaneously, even a simple weekly log, so the deadline never becomes a reconstruction exercise. Draft the T661 project descriptions alongside the T2 return, not after it. First-time claimants should seriously consider the CRA’s pre-claim consultation, which is free and lets you confirm that your work actually qualifies before you spend months documenting it. And put the actual deadline, computed from your own year end, on a calendar the day the year closes, with reminders at the six- and twelve-month marks.
The 18-month window feels generous until you watch a busy company spend 17 of those months on everything else. The credit is worth too much to lose on a calendar.
Not sure whether your R&D qualifies, or worried you are already cutting it close on a past year? We help small businesses find funding and prepare applications. Book a free consultation, and check whether your projects qualify with our funding eligibility calculator. Our consulting rate is $125 per hour, HST extra. The CRA’s Guide to Form T661 is the authoritative reference for the filing rules covered here.
New to the program? Read our first-time claimant’s guide to the SR&ED tax credit and our walkthrough of how to combine SR&ED and IRAP without shrinking either. For the bigger picture on combining programs safely, see our guide to stacking government funding without tripping double-dipping rules.
