Disability Tax Credit for Previous Years
How an approved DTC is applied to past years, and what else to claim back.
The short version
- If the DTC is approved for past years, CRA can reassess those returns to add the credit, generally back up to ten years.
- Tick the box on form T2201 asking CRA to adjust prior years, and CRA does it automatically for the approved years.
- The credit goes to whoever can use it: the person with the disability, a spouse, or a supporting family member. Each person's returns are reassessed separately.
- Families also get back-payments of the Child Disability Benefit, and may be able to add missed medical expenses and other claims.
- Most people can do this themselves. A company charging 15% to 30% of the refund is optional, not required.
Disability Tax Credit for Previous Years
The DTC is the closest thing in Canadian tax to finding money in an old coat. A parent of a child diagnosed at three, who applies when the child is twelve, can get nine years of credits at once, plus back-payments of the Child Disability Benefit. Five-figure refunds aren't unusual. Here's how the catch-up works.
Not approved yet? Start with disability tax credit eligibility and application.
How Far Back It Goes
The approval states which years the impairment met the criteria, based on the practitioner's certificate (Part B asks when the restriction began). CRA can then adjust returns for those years, but refunds are generally limited to the last ten calendar years. A condition that began in 2008 still gets you only 2016 to 2025 in refunds, if you apply in 2026. The full set of time limits is on how far back can you file taxes.
How to Get the Prior Years Adjusted
- On form T2201, ask CRA to adjust prior years (the applicant section has the question). After approval, CRA reassesses the returns for the approved years automatically.
- Check who claimed it. If a parent or spouse is the one transferring the credit, their returns are the ones that change. Make sure CRA knows who supported the person in each year.
- Look for related claims in those same years: medical expenses, attendant care, the disability supports deduction, the caregiver credit and larger child care limits. These aren't added automatically. Request them with Change my return or form T1-ADJ.
- Watch the notices of reassessment for each year. If one is wrong or missing, ask CRA, and object if needed.
What could the back years be worth?
Tell the assistant when the condition started, who supported the person, and roughly what the family earned. It estimates the federal credit for each year and lists the related claims to add.
What a Retroactive Claim Can Include
| Item | How it's recovered |
|---|---|
| Disability amount (and the under-18 supplement) | Automatic reassessment for approved years |
| Child Disability Benefit | Back-paid through the Canada Child Benefit for eligible years |
| Medical expenses not claimed before | Change my return or T1-ADJ, with receipts |
| Canada caregiver credit | Change my return or T1-ADJ |
| Higher child care limit ($11,000 for a child with the DTC) | Change my return or T1-ADJ |
| RDSP grants and bonds | Carry-forward rules apply; ask the RDSP issuer |
Details are on medical expense tax credit, Canada caregiver credit and child care expense deduction.
Doing It Yourself vs. Hiring a Firm
DTC firms advertise “we get you up to $50,000 back” and keep a share, often 15% to 30% by many reports. On a $30,000 retroactive refund, that's $4,500 to $9,000. A federal law that would cap these fees at $100 is in force on paper but suspended by a court injunction, CRA says. The application itself is free, and CRA does the prior-year adjustment for you. Where help earns its money is a refused claim, a complicated family history, or a large set of related claims. Then a flat fee beats a percentage.
If the Prior Years Weren't Approved
Sometimes CRA approves the DTC only from a recent year. If you think the impairment started earlier, ask the practitioner whether they can support an earlier date, and ask CRA to review. You can also object to the determination. See notice of reassessment: what to do for how objections work. The tax document analyzer reads the determination letter and tells you the deadline.
Retroactive DTC Questions
Can the disability tax credit be claimed for previous years?
Yes. If the DTC is approved for past years, CRA can reassess those returns. Refunds are generally limited to the last ten calendar years.
Do I have to refile old returns to get the retroactive DTC?
No. If you ask on form T2201 for prior years to be adjusted, CRA reassesses the approved years automatically. Related claims such as medical expenses must be requested separately.
How much is a retroactive disability tax credit worth?
It depends on the years approved and who claims it. Federally, the disability amount is worth roughly $1,400 to $1,450 a year in recent years, plus provincial credits and any under-18 supplement and Child Disability Benefit back-payments.
Should I use a company to claim the DTC retroactively?
It is optional. The application and the prior-year adjustment are free through CRA. Some companies charge a percentage of the refund; a legal fee cap exists but is suspended by a court injunction.
Sources: CRA, RC4064 Disability-Related Information (adjustments to prior years); DTC promoters restrictions (suspended); Tax refunds (ten-year limit). Checked October 2026. Promoter fee ranges are as commonly reported, not a CRA figure. Child Disability Benefit back-payment limits depend on CCB rules for each year.
Last reviewed October 4, 2026 against CRA and Government of Canada sources. How we check our facts.