Do common-law partners have to file taxes together in Ontario?
Tax filing is federal, not provincial. Under the Income Tax Act, you must report your relationship to the Canada Revenue Agency once you have lived with a partner in a conjugal relationship for twelve consecutive months, or immediately if you have a child together. After that point, the CRA treats you as common-law partners for tax purposes.
You do not file a single joint return — each person still files their own individual return. However, you must identify your partner on your return and report their net income, because many credits and benefits are calculated on combined family income. This affects the Canada Child Benefit, GST/HST credit, Ontario Trillium Benefit, RRSP spousal contributions, and various non-refundable tax credits.
If your relationship status changed during the year, you must notify the CRA by the end of the month following the change. Failing to update your status can result in repayment demands for benefits you were not entitled to receive. Your accountant or tax preparer can help you ensure your return accurately reflects your common-law status and optimizes the credits and deductions available to your household.
Key takeaways
- Tax rules are federal — CRA requires you to identify as common-law after twelve months of cohabitation.
- You file separate returns but report your partner's income for benefit calculations.
- Combined income affects the Canada Child Benefit, GST/HST credit, and other benefits.
- Notify CRA promptly when your relationship status changes.