“We’ve been living together for years, so doesn’t that make us common-law?” It’s one of the most common questions a family lawyer hears, and the honest answer is: usually, but the details matter. In Ontario, cohabitation is a specific legal concept, not simply a shared address, and whether you meet the legal definition can shape your rights to spousal support, property, and your estate.
Cohabitation Is More Than Living Under One Roof
Ontario’s Family Law Act extends certain rights and obligations to couples who have been cohabiting for at least three years, or for a shorter period if they have a child together. But the courts have made clear that cohabiting is not simply about sharing a lease.
Courts look at the substance of the relationship: whether the couple shares meals, shares a bed, splits household chores, exchanges gifts, cares for one another during illness, shares finances, and presents publicly as a couple. No single factor decides the question; the overall picture does.
This cuts both ways. Two people can be found to be cohabiting even if they keep separate residences. And a married couple can live in the same house, in separate bedrooms, no longer sharing meals or a life together, and still be considered separated in the eyes of the law. It’s common for spouses to remain under one roof for financial or childcare reasons long after the relationship itself has ended.
Why the Length of Cohabitation Matters
The three-year mark is the benchmark most Ontario family lawyers point to, but it isn’t the only one that matters:
- Spousal support for common-law partners
A common-law partner may be able to claim spousal support after separation if the couple cohabited continuously for at least three years, or for any length of time if they share a child. Support is never automatic; courts look at financial interdependence and any economic disadvantage suffered as a result of the relationship ending.
- Spousal support for married couples
Even where a couple is legally married, courts calculate spousal support based on the length of cohabitation, not the length of the marriage itself. The longer the cohabitation, the longer a support obligation is likely to last.
- Proving marriage breakdown
Couples seeking a divorce most commonly rely on having lived “separate and apart” for one year. Living separate and apart essentially means the couple has stopped cohabiting, even if, as noted above, they still share a house.
- Property Rights: Where Married and Common-Law Couples Differ Sharply
This is the area where the difference between marriage and cohabitation matters most, and where people are most often surprised.
Ontario’s property division regime under the Family Law Act applies only to married spouses. Marriage is treated as an economic partnership, and on separation each spouse is entitled to an equalization payment reflecting the value of property accumulated during the marriage. Married spouses also have an equal right to remain in the matrimonial home, regardless of whose name is on the title or lease.
None of this extends automatically to common-law couples. Living together, however long, does not by itself entitle one partner to a share of the other’s property. A cohabiting partner who is not on title, and who has no cohabitation agreement, has no statutory claim to that property at all.
That doesn’t mean a cohabiting partner is always without recourse. Where one partner has contributed money, labour, or effort that unfairly enriched the other’s property, courts can grant a remedy through unjust enrichment or a constructive trust. To succeed, the claimant generally needs to show a contribution to the asset, an expectation of an interest in it, and that it would be reasonable for the owner to have expected to share that interest. The remedy is typically a monetary award, though courts sometimes grant an interest in the property itself.
Cohabitation Agreements: Protecting Yourselves in Advance
Because the default legal protections for common-law couples are so much thinner than for married spouses, many cohabiting couples in Ontario choose to enter into a cohabitation agreement.
A cohabitation agreement is a domestic contract between two people who live together, or plan to, that sets out their respective rights and obligations. It commonly addresses:
- Ownership and division of property brought into or acquired during the relationship
- How household expenses and shared debts will be handled
- What happens to jointly held assets and debts if the relationship ends
- Whether spousal support will be paid, waived, or capped, and on what terms
One important limit: a cohabitation agreement cannot determine parenting arrangements or child support. Those issues are always decided based on the best interests of the child, regardless of what the parents agree to in advance.
To be enforceable, a cohabitation agreement must be in writing, signed, and witnessed. Because it deals with significant financial rights, each partner should have their own lawyer review it before signing, and many couples revisit the agreement periodically, particularly around milestones like buying a home together or having children.
Frequently Asked Questions
Three years is the most commonly used threshold, though a couple with a child together can qualify sooner for support purposes.
Yes. Courts look at whether the couple continues to function as a couple, not simply their address.
No. The three-year threshold is primarily relevant to spousal support eligibility under Ontario’s Family Law Act. Common-law partners do not automatically acquire the same property or equalization rights as married spouses simply because they have lived together for three years.
A cohabitation agreement can be helpful for couples who want to establish clear expectations about property, finances, debts, and spousal support. It can provide greater certainty if the relationship ends and may help reduce the potential for future disputes.
Key Takeaways
- Cohabitation is more than simply sharing an address.
- The three-year threshold is important for determining eligibility for spousal support, but it does not mean that every couple automatically becomes “common-law” after three years.
- Common-law couples do not automatically have the same property rights as married spouses.
- Couples can enter into a cohabitation agreement to establish financial and property arrangements.
- A cohabitation agreement cannot predetermine decision-making responsibility or parenting time.
