Common-law property rights in Ontario don’t come from a statute the way a married spouse’s do. Ontario’s Family Law Act gives married spouses automatic protections over a matrimonial home regardless of whose name is on title. A common-law partner gets none of that. What actually protects a common-law partner’s interest in a shared home comes from a different set of tools entirely: being named on title, a cohabitation agreement signed in advance, or, failing both of those, a constructive trust or unjust enrichment claim that a court has to decide on the specific facts. This guide walks through what each of those actually means, how a claim like that gets pursued, and what you can do before a dispute ever starts, alongside everything else a Toronto property situation involves in our complete Toronto real estate guide.
Common-law property rights in Ontario: the baseline
Our guide to the matrimonial home in Ontario covers this in detail. Stated once here rather than rebuilt: the Family Law Act’s matrimonial-home protections, equal possession regardless of whose name is on title, the requirement that one spouse consent before the other sells or mortgages it, the right to apply to court for exclusive possession, apply only to married spouses. A common-law partner gets no equivalent automatic right under these specific provisions, even after many years of living together in the same house. If the home is solely in one partner’s name, that partner can, as far as this part of the Family Law Act is concerned, sell or refinance it without the other partner’s consent.
That gap surprises a lot of people, because living together for years feels like it should create the same protections marriage does. It doesn’t, at least not through this particular statute. What actually protects a common-law partner runs through entirely different legal routes, covered below, and which one applies depends almost entirely on whether your name is on title in the first place.
What already protects you, regardless of marital status
If you’re named on title, as either a joint tenant or a tenant in common, you already have an enforceable ownership interest in the property, and that protection has nothing to do with whether you’re married. It comes from ordinary property law, the same rules that apply to any co-owners, siblings, friends, or business partners included. Our guide to joint tenancy versus tenants in common in Ontario explains what each form of co-ownership actually means and how they differ, since the two produce very different outcomes if the relationship ends or one partner dies.
This is the single most reliable way a common-law partner protects their interest in a shared home, and it’s also the one most people overlook, because it requires action before or at the time of purchase, not after a dispute starts. A partner who contributes to a down payment, a mortgage, or renovations but isn’t added to title is relying entirely on the much harder route covered next, instead of the straightforward ownership interest that being on title would have given them from the start.
What you can still claim if you’re not on title
A common-law partner who isn’t on title and contributed money, labour, or both to a home solely owned by the other partner isn’t automatically left with nothing. Ontario law allows a constructive trust or unjust enrichment claim, built on proving the titled partner received a benefit, the non-titled partner suffered a corresponding loss, and there’s no legal reason the titled partner should get to keep that benefit without compensating the other.
The leading case is the Supreme Court of Canada’s Kerr v. Baranow, 2011 SCC 10, which recognized what it called a joint family venture as a basis for this kind of claim. Where the couple genuinely pooled their efforts and resources toward common goals, integrating their finances and their lives rather than keeping everything separate, a court can find that a joint family venture existed and award a remedy tied to the share of the accumulated wealth the non-titled partner’s contribution actually helped create, not just a repayment of whatever money they put in directly. This is a genuinely fact-specific test, not a guarantee. Courts weigh how integrated the couple’s finances and lives actually were, and a relationship where both partners kept their finances largely separate is a much harder case to win than one where everything was genuinely shared.
How a claim like this actually gets pursued
A constructive trust or unjust enrichment claim goes through the courts, specifically the family branch of the Superior Court of Justice, not the Landlord and Tenant Board or any other administrative tribunal. This is a meaningful practical difference from a lot of the other property disputes this site covers. It isn’t a form you file and wait for a hearing date on. It’s a civil claim that typically needs a family lawyer, can take months or longer to resolve, and usually costs money in legal fees along the way, regardless of how the claim eventually turns out.
That cost and timeline is exactly why the two routes covered above, being on title from the start, or signing a cohabitation agreement, matter so much more than most people realize going into a relationship. Both avoid the need for a court to reconstruct years of financial history and relationship dynamics after the fact, which is precisely what a constructive trust claim requires a judge to do.
The agreement that prevents the dispute entirely
A cohabitation agreement, authorized under section 53 of Ontario’s Family Law Act, lets two people who live together, or plan to, set their own terms for property and other matters instead of leaving everything to a contested claim later. It can generally cover how property, including anything acquired after the agreement is signed, will be owned or divided if the relationship ends, whether either partner will pay spousal support and on what terms, and how shared expenses and debts get handled during the relationship. It can’t make binding decisions about children, and a court can still set an agreement aside later if one partner didn’t genuinely understand what they were signing or the terms turn out to be deeply unfair.
Without one, the rough default is that each partner keeps whatever is legally in their own name, with the constructive trust route above as the only way to challenge that. A cohabitation agreement doesn’t need to wait for a crisis. Couples sign them at the start of a relationship, when buying a home together, or at any point along the way, and the agreement is what turns an uncertain, expensive court claim into a settled, written understanding both partners already agreed to.
A different problem: forcing a sale between co-owners
None of the above is the same question as what happens when co-owners, common-law partners or otherwise, are both on title but disagree about selling. That’s a separate mechanic entirely, governed by Ontario’s Partition Act rather than anything covered in this guide. Our guide to the Partition Act in Ontario covers how any co-owner, including an unmarried partner who is on title, can force a sale even when the other owner won’t agree to one.
Frequently asked questions
Do common-law partners have any legal claim to a home they don’t own in Ontario?
Yes, but it doesn’t come automatically the way a married spouse’s matrimonial-home rights do. A common-law partner who isn’t on title and contributed money or effort to a home solely owned by the other partner can bring a constructive trust or unjust enrichment claim through the courts, built on the Supreme Court of Canada’s joint family venture test from Kerr v. Baranow. It’s a genuinely fact-specific claim, not a guaranteed outcome, and it requires proving the couple actually integrated their finances and lives rather than keeping everything separate. It’s a real legal route, just a much harder and more expensive one than simply being on title would have been.
What is a constructive trust claim in Ontario?
A constructive trust is a court-ordered remedy for unjust enrichment, used when one partner was enriched by the other’s contribution to a property, money, labour, or both, with no legal reason they should get to keep that benefit without compensating the other partner. In a common-law relationship, the Supreme Court of Canada’s joint family venture test from Kerr v. Baranow lets a court award a share of the property or its value tied to how much the couple’s finances and efforts were genuinely pooled together, rather than just a refund of specific amounts spent. It’s decided case by case in family court, based on the couple’s actual financial and relationship history.
Can I go to the Landlord and Tenant Board to claim an interest in my partner’s home?
No. A property claim between common-law partners, whether it’s a constructive trust claim or anything related to ownership of a shared home, goes through the family branch of the Superior Court of Justice, not the Landlord and Tenant Board. The LTB only hears landlord-tenant disputes under Ontario’s Residential Tenancies Act, which has nothing to do with a property-ownership claim between partners. A claim like this typically needs a family lawyer and goes through the regular civil court process, not a tribunal application.
Does a cohabitation agreement actually hold up in Ontario?
Generally, yes. Section 53 of Ontario’s Family Law Act specifically authorizes cohabitation agreements, and courts enforce them the way they enforce other family law contracts, provided both partners genuinely understood what they were signing and the terms aren’t deeply unfair to one side. A court can set one aside in limited circumstances, such as where a partner didn’t get proper financial disclosure before signing or didn’t understand the consequences. A properly prepared agreement, usually with each partner getting independent legal advice before signing, is far more likely to hold up than one drafted informally between the two partners alone.
If my name is on the title, am I already protected even though we’re not married?
Yes. Being named on title as either a joint tenant or a tenant in common gives you an enforceable ownership interest in the property under ordinary property law, and that protection doesn’t depend on whether you’re married at all. It’s the same protection any co-owner has, married or not, related or not. This is why getting added to title, at the time of purchase or afterward with the other owner’s agreement, is the most reliable way a common-law partner protects their interest in a shared home, rather than relying on a constructive trust claim after a dispute has already started.
Whether a cohabitation agreement, being added to title, or a constructive trust claim is the right route depends entirely on your own situation and what’s already in place, and that’s a conversation to have with a family lawyer before a disagreement forces the question. Get in touch with our team with questions about a specific property, and see our guides to the matrimonial home in Ontario, joint tenancy versus tenants in common, and the Partition Act in Ontario for the related situations this one often runs alongside, or browse the rest of our guides.