Updated Checked by the Tax-Services.ca editorial team How we check
There is no ADHD tax credit as such. What people mean is the disability tax credit, and the CRA decides it by how your condition limits daily life, not by the diagnosis. For 2026 the federal amount is $10,341, worth up to $1,448 in tax for an adult (for 2025 it was $10,138).
Does ADHD qualify for the disability tax credit?
Sometimes. The CRA doesn’t hand out approvals by diagnosis. Its mental functions page says eligibility rests on the effects of an impairment, “not a diagnosis or the presence of a medical condition”. ADHD isn’t named on that page, and neither is any other condition. So anyone telling you ADHD is automatically covered, or automatically refused, is guessing.
The page lists ten mental functions used in everyday life. Attention, concentration, goal-setting, judgment, memory and regulating behaviour and emotions are among them. You need a marked restriction in one or more, which means the person can’t do it, or needs at least three times as long as others, all or almost all of the time (generally 90% or more). It also has to last, or be expected to last, at least 12 months.
Sound strict? It is.
A hard year, or a child who struggles at school and at home, doesn’t meet the test by itself. The practitioner has to describe a restriction that is there almost all the time and has lasted a year or more, and the CRA weighs that description against its own criteria.
Who can fill in the medical part?
For mental functions, the CRA names three kinds of practitioner: a medical doctor, a nurse practitioner or a psychologist. If your child’s ADHD is followed by a paediatrician or a family doctor, that person can usually be the one. Someone who only sees you for therapy may not be on that list, so ask before you book the appointment.
It helps to bring the practitioner specifics. Not “Sam can’t focus”, but “Sam needs a parent to restart each step of getting dressed, every morning, and has for two years.” The form asks about effects, so examples with time frames carry more weight than labels.
What is the credit worth?
The credit is the disability amount times the lowest federal rate, which is 14% for 2026 (it was 14.5% for 2025). Children get a supplement on top. The table shows the 2025 return, because the supplement amount is confirmed on the CRA’s claiming page for that year only.
| 2025 return | Amount | Federal credit |
|---|---|---|
| Adult | $10,138 | $1,470.01 |
| Under 18 at the end of the year | $10,138 plus $5,914 supplement, $16,052 in all | $2,327.54 |
The credit only lowers tax you’d otherwise pay. If you owe nothing, it doesn’t produce a refund by itself, though you can move it to someone else, as the next section explains. The under-18 supplement can shrink when child care or attendant care costs are claimed for the same person. Your province adds its own credit on top, and the disability tax credit calculator shows a 2026 provincial figure.
How do you apply, and can it go back in time?
You apply on form T2201, the Disability Tax Credit Certificate. You complete one part and a medical practitioner completes the other, since the CRA relies on what they report. Only approved people can claim.
Once approved, you enter the amount on line 31600. If you were eligible in earlier years and never claimed, the CRA allows you to go back up to 10 years. That’s where the money is.
Take an adult approved for every year since 2021 with enough tax paid each year. The federal credits add up to $6,994.81 over 2021 to 2025. For a child under 18 throughout, the total is $11,075.09. We ran both through our engine, and each year’s credit hinges on how much tax was actually paid that year, so a low earner will get less.
What if the person doesn’t pay enough tax? Then some or all of the amount can be transferred to a supporting family member, such as a parent or spouse, who provides basic necessities (food, shelter or clothing). The tax credits calculator shows the other federal credits that might sit alongside it.
What else opens up with an approval?
Approval matters beyond the credit. The registered disability savings plan is open to people approved for the DTC. And the Canada Disability Benefit needs DTC approval, plus an age between 18 and 64 and a filed 2025 return.
Medical expense claims are a separate matter. We haven’t confirmed which ADHD related costs count, so we won’t list any. Check the CRA’s medical expenses page before you claim anything.
Mistakes that cost families money
Waiting is the big one. Every year you don’t claim is a year you might lose after the 10 year limit.
Another is assuming the form is a formality. The practitioner must describe the restriction in real terms, and a diagnosis letter alone doesn’t do that.
A refusal doesn’t always end things, either. But we didn’t confirm the appeal steps, so use the CRA’s own pages to see what your options are. Once the money arrives, put it to work with the tax refund calculator, which shows what a refund does to your year.
Where we got these figures
Eligibility wording comes from the CRA’s disability tax credit pages, including its mental functions eligibility page, checked in November 2026. The 2025 amounts come from the CRA’s claiming page, and the credit values in the table are our own arithmetic at the 14.5% blended federal rate for 2025. The 2026 amount and credit come from the Department of Finance tax measures document, because the CRA’s claiming page has no 2026 figure yet. The filed return requirement comes from the CRA’s Canada Disability Benefit eligibility page. This site is not connected to the CRA or any government.
Frequently asked questions
Is there a tax credit just for ADHD?
No. The credit that applies is the disability tax credit, and the CRA decides it by the effects of an impairment on daily life, not by diagnosis. ADHD is not named on the CRA's mental functions page, so nobody can promise approval or refusal in advance. You need a marked restriction in a mental function that lasts, or is expected to last, at least 12 months.
How much is the disability tax credit for 2026?
The 2026 disability amount is $10,341, worth up to $1,448 for an adult at the 14% lowest federal rate. For 2025 it was $10,138, worth $1,470.01 at the 14.5% blended rate, and a child under 18 got a $5,914 supplement, $16,052 in all. We could not confirm the 2026 child supplement on a CRA page.
Can I claim the disability tax credit for past years?
Yes, if you were eligible. Once approved, you can ask the CRA to adjust earlier returns for up to 10 years back. That is often where the money is, since an adult approved for every year from 2021 to 2025 could see federal credits of about $6,994.81 in our example, depending on the tax actually paid each year.
Who fills out form T2201?
You or your representative complete one part, and a medical practitioner completes the medical part. For mental functions the CRA names a medical doctor, a nurse practitioner or a psychologist. Specific examples with time frames, such as how long a task takes and how often help is needed, carry more weight than a diagnosis label.
Can a parent claim the credit for a child?
Yes. If the approved person does not need all of the credit, some or all of it can be transferred to a supporting family member, such as a parent or spouse, who provides basic necessities like food, shelter or clothing. Approval also opens the registered disability savings plan and, for ages 18 to 64, the Canada Disability Benefit.
- Canadian tax credits and government benefits explained
The difference between tax credits and benefits in Canada, how they're worked out from your return, and the calculators for the ones people claim most