The Disability Tax Credit — the gateway to the benefit
Almost every CDB problem that is not about income is really about the Disability Tax Credit. The CDB does not run its own medical assessment. Instead, it borrows the CRA's: you must be eligible for the DTC, which means the CRA has approved a Disability Tax Credit certificate for you. No certificate, no CDB — even if your daily life is plainly affected. Understanding the DTC is therefore the first practical step, before any CDB form is touched.
What the DTC requires
The DTC is for a person with a severe and prolonged impairment in physical or mental functions. In practice the CRA applies a marked-restriction test: the impairment must markedly restrict a basic activity of daily living (or, in combination, several activities), or the person must need life-sustaining therapy, and the restriction must have lasted, or be expected to last, at least 12 months. A medical practitioner completes Form T2201, the Disability Tax Credit Certificate, describing how the impairment affects daily life, and the CRA decides whether the test is met. The practitioner describes; the CRA decides. That division matters, because a supportive form does not guarantee approval, and a refusal can be challenged with more detail rather than treated as final.
Who can certify, and for how long
Different practitioners can certify different kinds of impairment — for example, a physician for most physical and mental functions, and other regulated practitioners (such as psychologists, occupational therapists, optometrists, audiologists and speech-language pathologists) for functions within their scope. The certificate is not always permanent: the CRA may approve it for a set number of years, after which a new Form T2201 is needed. Check the end date on your DTC notice. A CDB recipient whose certificate expires and is not renewed will stop meeting the gateway condition, and payments will be affected even if nothing else has changed.
The DTC is not the CDB
Confusing the two is common and costly. The DTC is a non-refundable tax credit: it reduces tax payable, and on its own it pays nobody a monthly amount. The CDB is a monthly cash payment that uses DTC eligibility as its gateway. You can hold a DTC certificate for years without ever receiving the CDB (for example, if your income is above the phase-out point), and you cannot receive the CDB without the certificate. Applying for the DTC is therefore step one for anyone who does not already hold one — and because CRA processing takes time, it should be started well before a CDB application is planned. If you already hold a valid certificate, that step is done; do not reapply for the DTC when what you need is the CDB application itself.
If the DTC is refused or expires
A refusal letter from the CRA states the reason, and the usual next step is a more detailed Form T2201 addressing exactly the restriction the CRA found unproven, or a formal objection. Keep copies of everything: the form, the practitioner's notes, the CRA notice, and the dates. For an expiring certificate, start the renewal before the end date, not after payments stop — the CDB has no grace period built into its gateway rule, and a gap in DTC coverage is a gap in CDB eligibility.