Common-Law Partners in Ontario Have No Automatic Property Rights. Here's What That Means.

In Ontario, common-law partners have no automatic right to share property at separation — regardless of how long they've lived together. The "3 years makes you common law" rule applies to spousal support eligibility only. If your partner owns the home and your name isn't on the title, you have no automatic claim to it. This article explains what the law actually says, where the myth comes from, and what protects you.

What "common law" actually means in Ontario

The 3-year threshold is real — but it does much less than most people assume.

Under section 29 of the Family Law Act R.S.O. 1990, c. F.3, a person qualifies as a "spouse" for spousal support purposes after cohabiting continuously for 3 years, or after any period if the couple has a child together. That's the entirety of what the threshold does in Ontario — it creates support eligibility, not property rights.

Property rights for married spouses are governed by Part I of the Family Law Act — the net family property and equalization regime. Part I applies only to married spouses. Common-law partners are not included. There is no equalization of net family property for common-law couples in Ontario, regardless of how long they've lived together, how much either partner contributed financially, or what either partner gave up.

Approximately 50–60% of Canadians incorrectly believe common-law partners have the same property rights as married spouses. This has been documented by the BC Law Institute, the Alberta Law Reform Institute, and the Law Commission of Canada. In Ontario, this belief is not a partial truth or an oversimplification — it's simply wrong.

What this means for the home

The most common and highest-stakes scenario: one partner owns the home, the other lives there, contributes to the mortgage informally, renovates, maintains the property. They build a life in it for years. They separate.

The non-titled partner has no automatic right to a share of the home's equity under Ontario law. No matter how long they lived there. No matter how many mortgage payments they made informally. No matter how many weekends they spent renovating.

The contrast with a married couple is stark. If a married partner owns a home that becomes the matrimonial home, the non-owning spouse has both a statutory right to live there under s. 26(1) and a right to participate in the equalization of its full value at separation. None of this applies to common-law couples. The home is entirely the titled partner's asset.

The only legal route to a property share without an agreement is unjust enrichment litigation. Under Kerr v. Baranow [2011] SCC 10, the Supreme Court of Canada established that a common-law partner can claim a share of property through unjust enrichment — but only by proving three elements: enrichment of the other partner, a corresponding deprivation to the claimant, and no juristic reason for the enrichment (no contract, gift, or other legal explanation). Courts may then award a monetary remedy or impose a constructive trust giving the claimant an ownership interest in specific property.

This process is inherently uncertain, takes years, and costs $50,000–$100,000 or more in legal fees with no guaranteed outcome. Practitioners consistently describe relying on unjust enrichment as the worst possible fallback compared to having a written agreement.

What about spousal support?

Support is where common-law partners do have rights — after 3 years of cohabitation (or sooner with a child). A qualifying common-law partner can claim spousal support under s. 29 of the Family Law Act using the same Spousal Support Advisory Guidelines framework as married couples.

But support and property are entirely separate legal regimes. Support compensates for economic dependency. It doesn't give you a share of assets, and it doesn't compensate for equity you helped build in someone else's home.

A partner who spent eight years providing unpaid domestic work, financing home improvements, and sacrificing career advancement — in a home she has no ownership stake in — may receive time-limited spousal support at separation. That is not equivalent to a share of the equity she helped create. The two outcomes are not comparable.

How this compares to BC

The variation in common-law property rights across Canada is wide enough that where you live matters enormously.

In British Columbia, since 2013 reforms to the Family Law Act SBC 2011, common-law couples have near-equal property division rights after 2 years of cohabitation. Property acquired during the relationship is divided. Pre-relationship property is excluded. British Columbia and Saskatchewan are the only provinces in Canada with full statutory common-law property division comparable to what married spouses receive.

In Ontario, no such reform has occurred. The gap between what people assume — equal rights after a few years — and what the law actually provides is wider in Ontario than almost anywhere else in Canada. If you've moved from BC to Ontario and your circumstances haven't changed, your legal rights have changed significantly.

Alberta offers some limited rights for "adult interdependent partners" after 3 years under the Adult Interdependent Relationships Act, but these fall well short of married-couple property division. Quebec offers nothing — common-law couples there have no property rights and no support rights whatsoever, a position the Supreme Court upheld in Quebec (Attorney General) v. A [2013] SCC 5 as not violating the Charter.

Ontario sits in the middle of this spectrum, but the practical effect for property purposes is the same as Quebec: you keep what's in your name.

What a cohabitation agreement does

A cohabitation agreement is a domestic contract under Part IV of the Family Law Act — the same framework as a marriage contract, but for unmarried couples. It fills the gap that the law leaves open.

A cohabitation agreement can define what each partner owns, how contributions to a jointly used home are treated, what each person is entitled to at separation, how spousal support is handled, and how debts are allocated. It converts the ambiguity of an unstructured common-law relationship into a clear, written financial framework.

It also does something unjust enrichment litigation cannot: it provides a "juristic reason" — a contract — that defeats unjust enrichment claims in either direction before they arise. It protects the property-owning partner from an unexpected constructive trust claim. It protects the non-owning partner by defining their entitlement explicitly, so they're not relying on expensive litigation to prove what they're owed.

Common-law unions dissolve at significantly higher rates than marriages. Approximately 65% of first common-law unions dissolve, compared to 24% of first marriages. The legal gap that a cohabitation agreement fills is one that a majority of common-law couples will eventually face.

If the couple later marries, the cohabitation agreement can typically be confirmed or updated into a marriage contract, maintaining the core property arrangements and recalibrating them to the married-couple regime.

For a full explanation of what a cohabitation agreement covers in Ontario, including what it can and can't do, see our dedicated guide.

Frequently Asked Questions

Does living together for 3 years give me property rights in Ontario?

No. The 3-year threshold under Ontario's Family Law Act applies only to spousal support eligibility under s. 29. It gives no property rights whatsoever. A partner who has lived with their spouse for 3, 5, or 15 years has no automatic claim to property held in the other partner's name. The only route to a property share is a cohabitation agreement or expensive unjust enrichment litigation.

What if I've been paying toward the mortgage for years?

Informal mortgage contributions don't create legal ownership. They may support an unjust enrichment claim at separation — but pursuing that claim requires expensive litigation ($50,000–$100,000+), years of uncertainty, and no guaranteed outcome. A cohabitation agreement that defines how contributions are treated at the outset is substantially more predictable and substantially cheaper.

What's the difference between common-law property rights in Ontario vs. BC?

Significant. In BC, common-law couples have near-equal statutory property division rights after 2 years of cohabitation under the Family Law Act SBC 2011. In Ontario, there are no automatic property rights regardless of the length of the relationship. If you've recently moved from BC to Ontario, your legal rights have changed even if your relationship hasn't.

Can I still get spousal support after a common-law separation in Ontario?

Yes — if you've cohabited for 3 years or have a child together, the lower-earning partner may be entitled to spousal support under s. 29 of the Family Law Act. But support and property are governed by entirely separate rules. Having support rights doesn't mean having property rights, and support doesn't compensate for equity in assets you helped build but don't own.

If we get married later, does that retroactively fix the property issue?

Marriage gives both spouses property rights under Part I of the Family Law Act going forward — but it doesn't retroactively create rights for the pre-marriage cohabitation period. A cohabitation agreement signed now, updated to a marriage contract when you marry, is the complete solution for both periods.

How much does a cohabitation agreement cost in Ontario?

Similar to a marriage contract. A full process — financial disclosure, drafting, and Independent Legal Advice for both parties — runs $2,400–$7,500+ through a traditional Ontario family lawyer. The cost is a fraction of unjust enrichment litigation, and substantially less than the value of the property rights it creates.

Start your cohabitation agreement

Ready to understand your options? Join the Parity waitlist to be first to know when we launch.

This article provides general information about Ontario family law and does not constitute legal advice. For advice specific to your situation, consult a licensed Ontario lawyer.