Key Points About the 12-Month Period
- Ending in the Tax Year: The 12-month period must end in the year for which you are filing your return. For example: - If you’re filing for the 2024 tax year, your chosen 12-month period must end on or before December 31, 2024. 
 
- Any Start Date: You can choose the start date for the 12-month period, as long as it doesn’t overlap with a period you’ve already claimed in a previous year. 
- Include All Eligible Expenses: Medical expenses paid during this chosen period can be included in your claim. 
How to Use the 12-Month Period Strategically
- Maximize Deductions: If you had higher medical expenses at different times in the year, select a 12-month period that captures the most costs. 
- Combine Expenses: You can group expenses for yourself, your spouse or common-law partner, and dependents within the same 12-month period. 
- Carry Expenses Forward: If you couldn’t use all expenses for the previous year, include those in the current year’s 12-month period as long as they fall within the eligible timeframe. 
Example of a 12-Month Period
- If you had significant medical expenses in late 2023 and early 2024, you could choose a 12-month period from February 1, 2023, to January 31, 2024, for your 2024 tax return. 
Why This Matters
Understanding how the 12-month period works ensures you can claim the highest possible amount for medical expenses, reducing your taxable income and maximizing your tax savings.
