Retroactive DTC claim: When a DTC application is approved, CRA can apply the credit to previous tax years — up to 10 years back — for any years in which the applicant was eligible. This often results in a one-time lump-sum refund ranging from $5,000 to $25,000 or more.
For a comprehensive overview of the DTC, see our Complete Guide to the Disability Tax Credit in Canada.
How Retroactive Claims Work
When CRA approves your DTC application, the approval includes a determination of when your eligibility began. If your condition met the DTC criteria in previous tax years, CRA can reassess those years and apply the DTC retroactively — resulting in a refund of taxes you overpaid.
The maximum retroactive period is 10 tax years. For example, if you are approved in 2026, CRA can reassess tax years as far back as 2016, provided your condition met the eligibility criteria during those years.
What Determines How Far Back You Can Claim
The retroactive period depends on two factors:
| Factor | How It Affects Your Claim |
|---|---|
| When your condition became eligible | Your medical practitioner indicates on the T2201 when the impairment began. CRA uses this date to determine the earliest eligible tax year. |
| The 10-year limit | CRA can only reassess the 10 most recent tax years, regardless of when the condition began. |
If your condition has been present for more than 10 years, you can still only claim back 10 years. If your condition began 5 years ago, you can claim back 5 years.
How the Refund Is Calculated
The retroactive refund is calculated by applying the DTC to each eligible tax year and determining the difference between what you paid and what you would have owed with the credit applied. The refund amount depends on:
- Your taxable income in each year
- Your province of residence (provincial credits vary)
- Whether you also qualify for the Child Disability Benefit (for children under 18)
- Whether the DTC was transferred to a supporting family member
Typical retroactive refunds range from $5,000 to $25,000, though amounts can be higher for families with children who qualify for the CDB supplement.
Maximizing Your Retroactive Claim
To maximize your retroactive refund:
- Establish the earliest possible eligibility date. Work with your practitioner to accurately document when your condition first met the DTC criteria.
- Ensure all eligible years are included. Verify that CRA has reassessed all applicable tax years.
- Claim the Child Disability Benefit retroactively. If your child qualifies, CDB payments can also be applied retroactively.
- Consider RDSP contributions. DTC approval may enable RDSP eligibility, which includes government grants and bonds.
Take our free eligibility assessment → | Call 1-844-MY-BENEFITS (1-844-692-3633)
This information is for educational purposes only. CRA makes all final eligibility determinations. Last updated: February 2026.
