Several important tax deductions and contribution opportunities expire on December 31 each year in Canada, and missing these deadlines can cost you hundreds or thousands of dollars in missed tax relief. The most significant year-end deadline is the RRSP contribution cutoff, which closes on December 31 for that tax year, followed by TFSA contribution room that must be used before the year ends, and various expense deductions like charitable donations and medical expenses that have strict calendar year or tax year limits. Planning ahead in the final months of 2026 helps you maximize available deductions and avoid the regret of a missed opportunity. December 31 is the magic date for several key tax benefits in Canada. Understanding what expires on this date and what has a later deadline is essential for smart tax planning. The most well-known year-end deadline is your RRSP contribution limit. You can contribute to your RRSP up to and including December 31, 2026, and claim that contribution on your 2026 tax return. After January 1, 2027, any contributions you make count toward your 2027 tax year only. Your available RRSP contribution room is shown on your CRA Notice of Assessment.
If you miss the deadline, your contribution counts toward next year's tax year instead. You don't lose your contribution room; it carries forward, but you lose the tax deduction for the current year and the opportunity for that year's tax-sheltered growth.
Yes, you can contribute to your TFSA anytime, but contributions made after December 31 count toward the next calendar year's contribution room. Your 2026 contribution room expires on December 31, 2026.
Charitable donations claimed on your 2026 tax return must be made by December 31, 2026. The donation must be complete and you must have a valid receipt from the registered charity.
Medical expenses can be claimed using either a 12-month period ending on the date you file your return, or the calendar year (January 1 to December 31). You choose the period that gives you the largest deduction.
Yes, FHSA contributions for the 2026 tax year must be made by December 31, 2026. Like RRSPs, FHSA contribution room carries forward if unused.