How a Cohabitation Agreement Should Address a Home You Buy Together in Ontario

Buying a home with a partner you're not married to feels a lot like buying a home with a spouse — same mortgage application, same closing table, same excitement. Legally, it isn't the same at all. Ontario gives married spouses an automatic set of property and matrimonial-home protections. Unmarried couples get none of that, no matter how long they've lived together or how the mortgage is structured. A cohabitation agreement is how you build those protections yourself.

If you're buying a home with a partner and haven't put anything in writing about what happens if you later separate, the home's fate will depend on whose name is on title, what you can prove about who paid for what, and general property law — not on a family law framework designed for exactly this situation.

Why This Needs Its Own Clause

For married spouses, Ontario's Family Law Act provides special treatment for the matrimonial home — both spouses have an equal right to possess it, and neither can sell or mortgage it without the other's consent, regardless of whose name is on title. None of that applies to unmarried couples. A home owned by unmarried partners is governed by ordinary property law and whatever the parties agreed to — which, without a written agreement, may be nothing at all.

This is one of the most consequential misconceptions in Ontario family law: unmarried partners do not get automatic property-sharing rights after any length of cohabitation. There is no point at which living together long enough creates a "common-law" equivalent to a married spouse's equalization claim. A partner who isn't on title, or who contributed less to the down payment, can be left with far less than they expect — or with a difficult, expensive claim to make under general trust or property law instead.

A cohabitation agreement's home clause exists to replace that uncertainty with a plan both partners agreed to in advance.

Key Terms Your Agreement Should Cover

• [ ] How the home is titled — joint tenancy, tenants in common in equal shares, or tenants in common in unequal shares reflecting actual contributions
• [ ] The down payment — who contributed what, and whether that contribution is treated as a loan, a gift, or an ownership share
• [ ] Ongoing costs — how the mortgage, property tax, insurance, and maintenance will be split, and what happens if one partner can't keep up their share
• [ ] Future contributions — how renovations or lump-sum mortgage paydowns by one partner will be credited if the relationship ends
• [ ] What happens on separation — whether one partner has a right of first refusal to buy out the other, a required sale process, or another mechanism
• [ ] A timeline for resolving the home if you separate, so neither partner is stuck in limbo
• [ ] What happens if you later marry — under the Family Law Act, a cohabitation agreement is automatically treated as a marriage contract once you marry each other, whether or not it was drafted with that in mind, so review it with your lawyer before the wedding to confirm the terms still make sense

If You Contribute Unequally

Few couples put in exactly equal down payments or exactly equal ongoing costs, which is precisely why this needs to be addressed explicitly rather than assumed. Common approaches include:

1. Unequal ownership shares on title — reflecting the actual proportion each partner contributed to the purchase
2. Equal title with a reimbursement clause — both partners are joint owners, but the agreement guarantees repayment of the larger contribution (with or without interest) if the home is sold or the relationship ends
3. A loan structure — the larger contribution is documented as a loan from one partner to the household, repayable on sale or separation, rather than an ownership stake

Whichever approach you choose, the key is documenting it while the numbers and everyone's intentions are still clear — reconstructing "who paid for what" years later, after a separation, is exactly the kind of dispute a cohabitation agreement is meant to prevent.

If the Relationship Ends

A good home clause maps out the process in advance, rather than leaving it to be negotiated under stress:

1. How the home's value will be determined (typically an appraisal, or an agreed process for choosing one)
2. Who has the right — or the first opportunity — to buy out the other's share, and by when
3. What happens if neither partner wants to keep the home, or neither can afford a buyout (usually a listing and sale process)
4. How outstanding contributions, credits, or loans under the agreement get settled out of the sale proceeds or buyout price
5. A reasonable timeline for each step, so the process doesn't stall indefinitely

What This Doesn't Replace

A cohabitation agreement's home clause works alongside — not instead of — your actual title documents, mortgage agreement, and any registered charges on the property. The agreement governs the arrangement between the two of you; it doesn't change what's registered on title or your obligations to the lender. Getting the title structure and the agreement's terms to actually match is an important step your lawyer should confirm.

Frequently asked questions