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If you searched for RD tax, you probably mean the R&D tax credit, which in Canada is the SR&ED program (scientific research and experimental development). We’re assuming that reading, since “RD tax” could also mean a road charge, and Canada has no single federal one. A qualifying Canadian-controlled private corporation (CCPC) can earn a 35% credit on eligible spending up to a yearly limit, and 15% above it.
How much is the R&D tax credit worth?
The CRA says the program gives two benefits: a deduction against income and an investment tax credit (ITC). The credit is where the money is. The rate depends on who you are and how much you spend.
| Claimant | Credit rate | Refundable? |
|---|---|---|
| CCPC, spending up to the limit | 35% | Fully, on current spending (for a qualifying corporation) |
| CCPC, spending above the limit | 15% | Partly, so check the CRA page |
| Individuals, trusts, partnerships, other corporations | 15% | Individuals get 40% of it back. Check the CRA for the rest |
| Eligible Canadian public corporations | 35% up to the limit, for years beginning after 15 December 2024 | See the CRA page |
People trip over the expenditure limit. The CRA’s ITC page shows $6 million for tax years beginning after 15 December 2024, and $3 million before that. Finance Canada first announced $4.5 million in December 2024, so older articles quote a different figure, and you should trust the CRA page over any of them.
What does the R&D tax credit look like on real numbers?
Say a CCPC spends $200,000 on qualifying current expenditures in a year. At 35%, the credit is $70,000, and it can come back as cash if the company qualifies for the full refund. A quick ballpark check is easy with the percentage calculator.
Now a bigger claim. Spend $6.5 million and, with a $6 million limit, the first $6 million earns 35% ($2,100,000) and the last $500,000 earns 15% ($75,000). That’s $2,175,000 in credits before any other rule cuts in.
And a small one for a person. A self-employed developer in Ontario who spends $20,000 on qualifying work at the 15% individual rate earns a $3,000 credit. Because individuals get 40% of it back, that’s $1,200 as a refundable piece and the rest used against tax owing. The percentages come from the table above, and the split between refunded and used is our own arithmetic, so confirm it on your return.
That covers the credit. The deduction is a separate benefit, so take an Alberta CCPC with $300,000 of business income. The corporate tax calculator shows $33,000 of tax at the 11% small-business rate. Deduct the $200,000 of R&D spending and taxable income drops to $100,000, which the tool taxes at $11,000. That’s $22,000 less. We haven’t modelled how the credit itself is treated afterwards, so treat this as the deduction only.
What work actually counts?
Not everything. The work has to be a systematic investigation in science or technology, carried out through experiment or analysis, aimed at resolving a technological uncertainty. That’s the CRA’s framing of it, and most rejected claims come from not showing that uncertainty. We couldn’t retrieve the CRA’s full list of excluded activities, so read its “what work is eligible” material before you assume a project qualifies.
Who can claim? The CRA’s SR&ED tax incentives page names corporations, individuals, trusts and partnerships doing eligible work. If you’re a sole proprietor, the self-employed tax calculator shows your baseline tax, though it doesn’t model SR&ED.
When do you have to file?
A corporation has up to 18 months after the end of the tax year in which the spending happened. An individual has 17 and a half months. You file Form T661 to describe the work and total the spending, plus Schedule T2SCH31 for a corporation’s credit. So a December 2026 year-end gives a corporation until June 2028. That’s a long window, and plenty of companies sit on it until the last few months, then scramble to rebuild what the team did and why, which is exactly when claims get thin. Don’t. Notes written while the project runs are far easier to defend than a story rebuilt later.
What records should you keep while the project runs?
Think of it as a lab notebook, even if your lab is a laptop. Write down what you were trying to do, what you didn’t know at the start, what you tried, and what happened. Keep dated versions of designs, test results and the odd failed attempt. Failures are good evidence that the answer wasn’t obvious.
Then tie the money to the work. Payroll for the people who touched the project, the hours they spent, and invoices for materials or contractors. A claim with clean timesheets reads very differently from one built on a rough guess in month 17.
Mistakes and limits
Assuming the 35% rate applies to everything is the most common one. It stops at the limit, and it needs CCPC status. The CRA page treats stand-alone and associated CCPCs separately, so if you’re part of a group, check whether you share one limit before you plan around the full amount.
Ordinary product development is another trap, since it’s not research. Building a routine feature with a known method is unlikely to qualify. Finance has also announced changes, such as restoring capital expenditures for property acquired on or after 16 December 2024. Those changes were enacted in 2026, so check the CRA for the details before relying on them.
Provinces run their own R&D credits too, and the CRA keeps a page that lists them. We haven’t confirmed any provincial rates, so we’ve left them out.
Where the numbers come from
Credit rates, the expenditure limit, refundable treatment and filing deadlines come from the Canada Revenue Agency‘s SR&ED pages, read in September 2026. The December 2024 announcement comes from the Department of Finance Canada. Tax figures in the example come from the calculator’s 2026 data. This site is independent and has no tie to the CRA.
Frequently asked questions
What does RD tax mean in Canada?
Most likely the R&D tax credit, called SR&ED. We've assumed that reading because Canada has no single federal road tax.
What is the R&D tax credit rate for a CCPC?
35% on qualified spending up to the expenditure limit, and 15% above it.
What is the expenditure limit?
The CRA shows $6 million for tax years beginning after 15 December 2024, and $3 million for earlier years.
When is the SR&ED claim due?
Corporations have up to 18 months after the end of the tax year. Individuals have up to 17 and a half months.
Can a sole proprietor claim SR&ED?
Yes, individuals doing eligible work in Canada can claim, at the 15% rate with 40% of that credit refundable.
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