Cohabitation Agreement in Ontario: What It Covers and Cannot

Moving in with a partner usually feels like a happy, practical step, not a legal one. But if you are not married, the law treats your property and your finances differently from a married couple's, and a written agreement is one way to set your own terms.

This article explains what a cohabitation agreement can and cannot cover in Ontario, how it differs from a marriage contract, and what helps it hold up. It is general information, not advice on your situation.

What a cohabitation agreement is

The Ontario government describes a marriage contract as a legal document signed by couples before they get married to protect their rights if they split up, including rights to property. Couples in a common-law relationship can sign a similar document called a cohabitation agreement.

In plain terms, it is a written plan, made while things are going well, for what happens if the relationship ends. It lets you decide the terms yourselves instead of leaving them to the default rules or to a judge.

Ontario lists five kinds of domestic contract: marriage contracts, cohabitation agreements, paternity agreements, separation agreements and family arbitration agreements.

What it can cover, and what it cannot

Marriage contracts and cohabitation agreements can cover support, property division and who moves out on separation. They cannot say who has decision-making responsibility or parenting time for the children.

That limit matters. When a court makes a parenting or contact order under the Divorce Act, it takes into consideration only the best interests of the child, with primary consideration to the child's physical, emotional and psychological safety, security and well-being. Your agreement cannot take that decision away from the court, so it is better to leave children's arrangements out of it or to treat them as a statement of intentions only.

Child support works the same way. A child support order must follow the applicable guidelines, so child support is set by the court under the Guidelines, not fixed by the parents' contract.

How it differs from a marriage contract

The main difference is the starting point. Married spouses are subject to equalization: property acquired during a marriage must be split equally when the marriage ends for any reason, and courts can divide differently only in very special situations. A marriage contract is a way for spouses to change that outcome for themselves.

Common-law couples are not legally required to split property acquired while living together. Household items and other property belong to the person who bought them, and they do not share in the increase in value of property brought into the relationship. A cohabitation agreement lets you set different terms, for example to share certain assets or to confirm that each person keeps what they bring.

Who counts as living together can itself be a question. For Family Law Act purposes, to cohabit means to live together in a conjugal relationship, whether within or outside marriage. A lack of a shared residence is not determinative, but there needs to be some element of living together under the same roof.

Making the agreement hold up

There are formalities. Both partners must sign the agreement in front of a witness, and the witness must also sign. Any later change must also be in writing and witnessed.

An informal understanding does not change a signed contract. In one Court of Appeal for Ontario decision involving a cohabitation agreement, a later informal arrangement did not amend the contract because it was not in writing, signed by the parties and witnessed.

Ontario's guidance advises that each partner use a different lawyer and that the partners exchange financial information before signing. These steps also matter because a court can set aside a domestic contract, or a provision in it, if a party failed to disclose significant assets or significant debts or other liabilities that existed when it was made, or if a party did not understand the nature or consequences of the contract.

• Full financial disclosure by both partners before signing
• A separate lawyer for each partner
• Signatures from both partners and a signed witness
• Plain wording, so both of you understand what you are agreeing to
• Written, witnessed changes whenever your plans change

What a court does with it later

Once signed, the contract must be followed. If the spouses separate and disagree about it, a judge may need to decide.

Setting a contract aside is a two-step process. First, the person asking must show one of the listed circumstances, such as non-disclosure, not understanding the contract, or a contract-law ground, and that is necessary but not sufficient. Second, the court decides whether to exercise its discretion to set the agreement or provision aside, and fairness can be considered at that stage.

A court may set aside a contract or a provision in it in its entirety. It does not let the court carve particular assets out of an agreement or amend it. In the decision mentioned above, property clauses of a cohabitation agreement were set aside because the trial judge found overwhelming evidence that neither party understood the consequences. The spousal support waiver in the same contract was not set aside, because the trial judge found no particular unfairness from it.

If you want support terms enforced by the Family Responsibility Office, the contract must be filed with the Ontario Court of Justice or Superior Court of Justice using form 26B, and then registered with FRO.

What to do next

Start by talking openly about what each of you owns, owes and expects. Then gather the paperwork that shows it.

• List your assets, debts and income, and share them with your partner
• Decide what you want to say about property, support and who stays in the home
• Each book time with your own lawyer before signing
• Leave children's parenting arrangements to be decided by the best interests of the child
• Sign in front of a witness who also signs, and keep a copy each
• Plan to review the agreement if your circumstances change, and make any change in writing with a witness

A family lawyer can confirm how these rules apply to your relationship, especially if you own a home, a business or have children from a past relationship.

Frequently asked questions