Key numbers (2025 tax year): The base federal DTC is worth approximately $9,428 in credits for adults. For children under 18, an additional child supplement of approximately $5,500 is available — bringing the total federal DTC value to roughly $14,900 per year. Many parents claim the base amount but miss the supplement entirely.
If your child has an approved Disability Tax Credit, you may be entitled to significantly more than you are currently claiming. The child supplement is an additional non-refundable tax credit available to parents and supporting persons of children under 18 who qualify for the DTC — and it is one of the most commonly missed credits in the Canadian tax system.
What Is the Child Supplement?
The child supplement is an additional amount added to the base DTC for individuals under 18. It is designed to recognize the extra costs associated with caring for a child with a disability — costs that adults with disabilities typically bear themselves.
2025 federal amounts (approximate):
- Base DTC: $9,428
- Child supplement: $5,500
- Total federal DTC for a child under 18: ~$14,900
These amounts are indexed to inflation and increase slightly each year. Provincial DTC amounts add further value on top of the federal credit.
Important restriction: The child supplement is reduced if you claimed child care expenses or attendant care expenses for the same child in the same tax year. CRA applies a formula to ensure the supplement is not double-counted with other care-related credits.
Who Can Claim the Child Supplement?
The child supplement can be claimed by the parent or supporting person who claims the child's DTC transfer. The child must:
- Be under 18 years of age at the end of the tax year
- Have an approved DTC on file with CRA
- Be a dependant of the person claiming the supplement
If the child has no taxable income (which is almost always the case for children), the full DTC — including the supplement — is transferred to the parent or supporting person.
The Child Disability Benefit (CDB): A Separate but Connected Program
The DTC approval for your child also unlocks the Child Disability Benefit (CDB), which is a separate monthly payment administered through the Canada Child Benefit system.
CDB amounts (July 2025 to June 2026): Up to $3,411 per year ($284.25 per month) per eligible child.
The CDB is income-tested — higher-income families receive a reduced amount. But unlike the DTC itself, the CDB is a cash payment, not just a tax reduction. It is paid monthly as part of your CCB payment.
To receive the CDB: Your child must have an approved DTC, and you must be receiving the Canada Child Benefit. CRA will automatically calculate and add the CDB to your monthly CCB payment once the DTC is approved.
Retroactive Claims: How Far Back Can You Go?
If your child has had an approved DTC for multiple years but you did not claim the full child supplement, you can file T1-ADJ adjustments for up to 10 prior tax years.
Similarly, if your child's DTC was approved recently but they have been eligible for several years, you can apply for retroactive DTC approval and then file retroactive tax adjustments.
Example: A parent of a child with autism who was approved for the DTC in 2024 but has been eligible since 2016 could potentially claim 8 years of retroactive credits — including the child supplement for each year the child was under 18. At approximately $14,900 per year in federal credits, the retroactive refund could be substantial.
CDB retroactive payments: CRA can also issue retroactive CDB payments for up to 10 years, based on the retroactive DTC approval period.
What Happens When Your Child Turns 18?
When your child turns 18, the child supplement is no longer available. However:
- The base DTC continues to apply (approximately $9,428 per year)
- The DTC can still be transferred to a supporting parent if the young adult has limited income
- The young adult becomes eligible for the Canada Disability Benefit (CDB) — the new federal program paying up to $200/month for working-age adults with an approved DTC
You do not need to reapply for the DTC when your child turns 18 — the existing approval continues. However, you should review the claiming strategy to ensure you are maximizing the available credits.
Common Conditions That Qualify for the Child DTC
The DTC for children is most commonly approved for:
- Autism spectrum disorder — particularly where the child requires significant support with daily activities
- ADHD — where executive function impairments cause a marked restriction in mental functions necessary for everyday life
- Down syndrome and intellectual disabilities
- Cerebral palsy and physical mobility impairments
- Type 1 diabetes — qualifying under the life-sustaining therapy category (insulin management)
- Severe learning disabilities affecting basic mental functions
- Hearing or vision impairments of sufficient severity
How My Benefits Canada Helps Families
We work with parents to assess eligibility, coordinate with pediatricians and specialists to complete the T2201, and manage the full retroactive adjustment process — including both the DTC child supplement and the CDB.
Start your free eligibility assessment — we will review your child's situation and let you know what your family may be entitled to.
Frequently Asked Questions
What is the child supplement for the DTC? It is an additional federal tax credit of approximately $5,500 per year (2025) for children under 18 with an approved DTC, on top of the base DTC of approximately $9,428.
Can I claim both the child supplement and the Child Disability Benefit? Yes. The child supplement is a tax credit, while the CDB is a monthly cash payment. Both are available to families with an approved child DTC.
What happens to the child supplement if I claimed child care expenses? The child supplement is reduced by the amount of child care or attendant care expenses you claimed for the same child. CRA applies a formula — you may still receive a partial supplement.
Can I claim the child supplement retroactively? Yes. You can file T1-ADJ adjustments for up to 10 prior tax years to claim the child supplement for years you missed.
Does the child need to be living with me to claim the supplement? The child must be your dependant, but does not necessarily need to live with you full-time. Shared custody arrangements are handled on a proportional basis.
