Medical Expense 12-Month Rule — Pick the Best 12-Month Window Instead of the Calendar Year
What Is It?
CRA lets you claim medical expenses for any 12-month period ending in the tax year, which can produce a much larger credit than sticking to January through December.
Do I Qualify?
- You paid eligible medical expenses for yourself, your spouse, or an eligible dependant
- The expenses fall within a 12-month period ending in the tax year
- The expenses were not already reimbursed or claimed elsewhere
- You can document the payment dates and amounts
How To Use It
- List all eligible medical expenses by payment date.
- Test different 12-month windows ending in the tax year.
- Use the window that gives the largest net claim after the income threshold.
- Keep the receipts organized by date.
What Most People Don’t Know
- Many people lose money by automatically using the calendar year.
- This rule is especially valuable after surgery, fertility treatment, major dental work, or a cluster of prescription costs.
- The payment date matters more than the service date for many claims.
Frequently Asked Questions
Is this automatic?
A: No. You choose the window when you prepare the return.
What documents help most?
A: Receipts with payment dates are the key records.
Where do I start?
A: Start by sorting all eligible expenses into date order before filing.
What is the biggest trap?
A: The biggest trap is using January to December out of habit when a different 12-month window is better.