Cohabitation Agreements in Ontario: The 'Prenup' for Common Law Couples
Protect your assets before you move in together. Define property rights, financial obligations, and what happens if you split.
Contract Strategy reviewed by Deepa Tailor, Principal Lawyer. Updated March 2026 to reflect Family Law Act requirements for domestic contracts.
Too Busy to Read? The 30-Second Answer:
The Risk: Common law partners in Ontario have ZERO automatic property rights. If you aren't on the deed, you don't own the home.
The Fix: A Cohabitation Agreement allows you to opt-out of the default rules and define exactly who owns what (house, pets, debts) if you split.
The Rule: For the agreement to be binding, you need Financial Disclosure and Independent Legal Advice (ILA). No napkins.
Forward-Thinking Love
Moving in together is a financial merger. It's not unromantic to protect your down payment or your pension, it's reckless not to.
A Cohabitation Agreement is a legally binding contract between unmarried partners that defines property rights, financial obligations, and what happens if the relationship ends. Think of it as a "prenup" for common law couples.
The Disruptor Angle:
"Moving in together is a financial merger. It's not unromantic to protect your down payment or your pension, it's reckless not to."
Unlike married couples, common law partners in Ontario have no automatic right to property division. A Cohabitation Agreement lets you create your own rules before emotions and lawyers get involved.
When Do You Become "Common Law"?
In Ontario, "common law" status depends on what you're talking about. The rules are different for spousal support versus property rights:
3 Years
For Spousal Support Obligations
After living together continuously for 3 years, you may have obligations to pay (or rights to receive) spousal support.
1 Year (with Child)
For Spousal Support
If you've lived together for 1 year and have a child together, spousal support obligations may apply.
Never
For Property Rights
Common law partners have ZERO automatic property rights in Ontario, regardless of how long you've lived together—unless you sign an agreement.
Critical Distinction:
Living together for 10 years doesn't give you rights to your partner's house, pension, or investments. If you're not on the deed, you don't own it. A Cohabitation Agreement is the only way to create property rights.
What the Agreement Covers
A well-drafted Cohabitation Agreement addresses the financial realities of living together and separating. Here's what you can include:
The Home
Who keeps it if you split? Does the other person get equity for renovations, mortgage payments, or sweat equity?
Note: Common law partners don't have "matrimonial home" rights under the Family Law Act. If you're not on the deed, you can be asked to leave immediately.
Joint Assets
How to split furniture, vehicles, joint bank accounts, and other shared property. Define what's "yours," "mine," and "ours."
Debts
Who's responsible for credit card debt, student loans, or the mortgage? Protect yourself from your partner's financial baggage.
Heritage & Inheritance
Keep family money, heirlooms, or gifts from parents separate. Ensure your inheritance doesn't become "shared property."
Spousal Support
You can waive or limit spousal support obligations (though courts may override this if it's unconscionable).
Pets
Yes, you can include custody arrangements for pets. Courts treat them as property, but you can define who keeps the dog.
The "Marriage" Clause: Efficiency Bonus
Here's the smart part: A Cohabitation Agreement automatically becomes a Marriage Contract if you get married later (unless you specify otherwise). You don't need to draft a new prenup, it's already done.
How to Draft It: The Rules
A Cohabitation Agreement isn't valid just because you both signed it. Ontario courts will throw out agreements that don't meet strict legal requirements. Here are the three pillars of enforceability:
Full Financial Disclosure
Both partners must disclose all assets, debts, income, and liabilities. This includes:
- Bank accounts, investments, RRSPs, pensions
- Real estate, vehicles, business interests
- Credit card debt, student loans, mortgages
Why it matters: If you hide assets or lie about your financial situation, the entire agreement can be set aside by a court.
Independent Legal Advice (ILA)
Each partner must have their own lawyer review the agreement and explain:
- What rights you're giving up
- Whether the terms are fair
- The legal consequences of signing
You cannot share a lawyer. Each lawyer must sign a certificate confirming they provided ILA. Without this, the agreement is vulnerable to being overturned.
Witnessed Signatures
The agreement must be signed in front of a witness (who is not a party to the agreement). This ensures formal execution and prevents claims of forgery.
Pro tip: Your lawyer can act as the witness, making the process seamless.
Timing Matters: Sign Before the Moving Truck Arrives
Duress claims happen when one partner feels forced to sign at the last minute. Courts are skeptical of agreements signed on moving day or under pressure. Draft and sign your Cohabitation Agreement well before you move in together.
Frequently Asked Questions
Protect Your Assets. Protect Your Relationship.
A Cohabitation Agreement isn't about planning for failure—it's about protecting what you've built and ensuring fairness if things don't work out. Let's draft an agreement that works for both of you.
Serving common law couples across Ontario: Toronto, Mississauga, Oakville, Burlington, Hamilton, and beyond.