One reason people set the Disability Tax Credit aside is a reasonable one: they do not pay much income tax, so a tax credit sounds like it is not for them.
That reasoning is understandable and it costs families a great deal of money, because the credit itself is the smallest part of what approval does.
What it is, precisely
The DTC is a non-refundable tax credit. It reduces income tax payable. The Canada Revenue Agency states plainly that if the credit is more than you owe, it will not refund the remainder.
Unused amounts can be transferred to a supporting family member, someone you depend on for at least one of the basic necessities of life: food, shelter or clothing. But they are not paid out as cash.
So on its own terms, a family with no tax payable gets little directly. The value is in the gate it opens.
What approval unlocks
CRA lists four things that require DTC approval.
The registered disability savings plan
A long-term savings vehicle for a person approved for the DTC, with contributions permitted until the end of the year the beneficiary turns 59. For a family planning past their own lifetime, this is usually the single most valuable consequence of approval.
The Canada Disability Benefit
New, federal, and it requires DTC approval. For July 2026 to June 2027 the maximum is $204.20 per month, assessed on the 2025 tax return.
| Test | Figure |
|---|---|
| Age | 18 to 64 |
| Income threshold, single | $23,000 |
| Income threshold, couple | $32,500 |
| Working income exemption, single | $10,210 |
| Working income exemption, combined | $14,294 |
| Reduction above the threshold | 20 cents per dollar |
You and your spouse or partner must both have filed your 2025 return.
The child disability benefit
For July 2026 to June 2027, up to $3,480 a year, $290 a month, for each child eligible for the DTC. If you already receive the Canada Child Benefit for a DTC-eligible child, it arrives automatically without a separate application.
The Canada Workers Benefit disability supplement
For the 2025 tax year, a maximum of $843.
The eligibility test
There are nine categories: walking, mental functions, dressing, feeding, eliminating, hearing, speaking, vision, and life-sustaining therapy.
The marked restriction test, in CRA's words, is that you are "unable to do the activity, or it takes 3 times longer than someone of similar age without the impairment, even with the use of appropriate therapy, medication, and devices." It must be present "all or almost all of the time (generally at least 90%)" and have lasted or be expected to last at least 12 continuous months.
The cumulative effect test matters for people who are not clearly marked in any one category: limitations in two or more categories count if together their effect is as severe as a marked restriction in one. Life-sustaining therapy cannot be combined this way; the other eight can.
Mental functions is the category most often argued and most often misunderstood. CRA's list of mental functions necessary for everyday life is: adaptive functioning, attention, concentration, goal-setting, judgment, memory, perception of reality, problem-solving, regulating behaviour and emotions, and verbal and non-verbal comprehension.
For life-sustaining therapy, the therapy must be needed at least twice a week and average at least 14 hours a week. CRA states that people with Type 1 diabetes meet the criteria under this category.
How to apply
Form T2201, the Disability Tax Credit Certificate, in two parts.
- Part A is completed by the person with the impairment or their legal representative, online in a CRA account or by phone. You then receive a reference number, valid for up to 12 months and usable only once.
- Part B can only be completed by a medical practitioner, who enters that reference number and submits it electronically.
Which practitioner depends on the category.
| Practitioner | May certify |
|---|---|
| Medical doctor, nurse practitioner | All impairments |
| Optometrist | Vision |
| Audiologist | Hearing |
| Occupational therapist | Walking, feeding, dressing |
| Physiotherapist | Walking |
| Psychologist | Mental functions |
| Speech-language pathologist | Speaking |
If your practitioner charges to complete the application, that is your cost, though you may be able to claim it as a medical expense.
Ten years back
This is the part people miss most.
For a family where a supporting parent or spouse did pay tax across those years, a retroactive adjustment can be substantial.
If you are on AISH or ADAP in Alberta
Read this section carefully, because it is where good news and bad news sit together.
The DTC is not an eligibility requirement for AISH or ADAP. But applying for federal programmes effectively is one. Alberta requires that you and your spouse or partner apply for all other government programmes and income you may be eligible for, including federal programmes, and requires recipients to report the outcome.
And the Canada Disability Benefit is treated as non-exempt income for AISH recipients. Alberta's wording is that recipients "will continue to receive the same overall monthly support that they do today."
Put plainly: for someone on AISH, being approved for the Canada Disability Benefit does not generally increase total monthly income. Applying is still required, and not applying costs $200 a month.
Two things soften it, and they are connected. Alberta will cover the cost of the DTC medical assessment for eligible clients, and the federal government has announced its intention to make a one-time supplemental payment of $150 by March 2027 to everyone approved for the Canada Disability Benefit, to offset the cost of the DTC medical assessment. The two are linked deliberately: an AISH client whose assessment Alberta paid for repays the programme once that $150 arrives. No application is needed for the supplement, and anyone who received a Canada Disability Benefit payment before the change is eligible, even if they are no longer receiving payments.
And the RDSP, the ten-year retroactive claim and the child disability benefit sit outside that interaction entirely. They are why the DTC is still worth pursuing.
Where this sits with us
We help people prepare and organise DTC applications: making sure the description of function is accurate and complete, that it reflects ordinary days rather than best ones, and that the practitioner completing Part B has what they need.
We are not tax advisers and we do not prepare tax returns. For the retroactive adjustment side, an accountant is the right person. We will say so.
Talk to us if you are not sure whether it is worth applying. Usually it is.