The medical expense tax credit (METC) is a non-refundable federal tax credit for eligible medical expenses, claimed on lines 33099 and 33199 of your return. Premiums you pay to a private health services plan — which includes individual health and dental insurance — are eligible medical expenses, alongside many out-of-pocket costs your plan does not reimburse. You can claim expenses paid in any 12-month period ending in the tax year, and the credit applies to the amount above the lesser of 3% of your net income or a fixed threshold the CRA sets each year ($2,834 for the 2025 tax year). Because it is non-refundable, it can reduce the tax you owe but will not create a refund on its own.