The 3 % rule that decides whether your medical receipts are worth claiming

A shoebox of pharmacy receipts, a dental invoice and a new pair of glasses can feel like a lot of money, and often is. Whether any of it reduces your tax depends on a single comparison that many households never make: the total against a threshold set by your own net income. Below the threshold, nothing is claimable. Above it, every dollar counts, and a few decisions about who claims and over which months can change the outcome noticeably.

The threshold: 3 % of net income, or a dollar cap

The medical expense tax credit is a non-refundable federal credit claimed on line 33099 of the return. You add up eligible expenses, then subtract the lesser of 3 % of your net income (line 23600) or a fixed dollar amount, which is $2,834 for the 2025 tax year and $2,890 for 2026. Only what remains earns the credit. The federal credit is that remaining amount multiplied by the lowest federal tax rate, which is 14 % for 2026 (see our guide to the 2026 brackets), plus a separate provincial or territorial credit calculated on Form 428.

The dollar cap takes over at a net income of roughly $94,500 for 2025 and roughly $96,300 for 2026; above that, 3 % of income exceeds the cap, so the cap is used. Below it, the 3 % rule applies, which is why the credit tends to be more useful at lower and middle incomes. Quebec residents file a separate provincial return, and Quebec's own medical expense credit follows its own rules.

Any 12 months, as long as they end in the tax year

The expenses do not have to fall in the calendar year. You can choose any 12-month period ending in the tax year, provided the expenses were not claimed on a previous return. The CRA's own example uses 1 July 2024 to 30 June 2025 for a 2025 return. This matters when a run of costs, such as orthodontic work or a hospital stay, straddles December: grouping them into one 12-month window gets you over the threshold once, rather than falling short twice.

What is on the list, and what is not

The CRA publishes a long alphabetical list of eligible expenses. The common ones for a household are:

• Prescription drugs that can only be obtained with a prescription and are recorded by a pharmacist. Over-the-counter products are not eligible even if a doctor writes them down, and vitamins are excluded apart from vitamin B12 therapy for pernicious anaemia.
• Dental services, including dentures and implants, but not purely cosmetic work.
• Prescription eyeglasses and contact lenses, as devices that correct eyesight.
• Premiums to a private health services plan, including the employee share of a workplace plan, provided at least 90 % of the premiums go toward eligible medical expenses.
• Attendant care and care in a facility, subject to separate rules on certification and on how the claim interacts with the disability tax credit.
• Travel for treatment when equivalent services were not available nearby. At 40 km or more one way, public transport fares count, or vehicle costs where public transport is not readily available; at 80 km or more, reasonable meals, accommodation and parking can be added.

Cosmetic procedures qualify only when they are medically or reconstructively necessary. General fitness, gym memberships and most health products bought without a prescription are not on the CRA's list of eligible expenses.

Illustrative. Uses the CRA's 2025 threshold of $2,834 and the 3 % of net income rule for line 33099. The federal credit is the final row multiplied by the lowest federal rate; provincial credits are calculated separately and vary.

Claiming for a spouse and for dependants

Line 33099 covers expenses for yourself, your spouse or common-law partner, and children under 18 at the end of the year. Expenses for other dependants, such as a child who is 18 or older, a parent or a grandparent who relied on you for support, go on line 33199, and here the threshold is calculated separately for each dependant using that person's net income.

Because the threshold is tied to the claimant's net income, a couple can usually pool the family's receipts on one return, and it is often the lower-income spouse who should claim. In the CRA's example, a spouse with $42,000 of net income could claim more than one with $55,000 on the same receipts. Run both versions before filing.

The question is not how much you spent on health, but how much you spent above 3 % of your income.

A refundable top-up for lower-income workers

Separately from the credit, the refundable medical expense supplement on line 45200 can put money back even when no tax is owing. For 2025 it requires that you were 18 or older, resident in Canada all year, had at least $4,390 of employment or self-employment income, and had adjusted family net income below $63,374. The maximum supplement is $1,504 for 2025 and it is reduced once family net income passes $33,294. For 2026 those figures rise to $4,478, $1,534 and $33,960.

Good to know

Dental work paid for by the Canadian Dental Care Plan or an insurer cannot be claimed; only the portion you actually paid counts. Certain home renovations for mobility may qualify either here or under the home accessibility credit, and in some cases both.

Who this matters for, and what to check

• Households with modest income and a run of health costs: work out 3 % of net income; if your receipts exceed it, the credit is live.
• Couples: total the family's receipts and test the claim on each spouse's return; the lower-income spouse often comes out ahead.
• Anyone paying workplace health premiums: the employee share shown on your pay stubs or T4 is usually an eligible expense that people forget.
• Anyone supporting an adult child or parent: use line 33199 and that person's own net income for the threshold.
• Everyone claiming: keep receipts, prescriptions and travel records; the CRA does not need them with the return but can ask for them later.

The takeaway

The medical expense credit rewards costs above the lesser of 3 % of net income or $2,834 (2025) or $2,890 (2026). Choose the 12-month window that bunches your expenses, put the claim on the return where the threshold is lowest, remember dependants' separate line, and check whether the refundable supplement applies if your working income is low. The receipts you already have decide the rest.