What Makes a Separation Agreement Legally Binding in Ontario?

You and your partner have agreed on how to divide things after separating, and now you want to know whether a written deal will actually hold up. Maybe you found a template online, or maybe you reached an agreement through mediation and wonder what happens next.

In Ontario, an agreement is binding only if it meets a short list of formal requirements, and it can still be challenged if the way it was reached was unfair. This article walks through both, so you can check your own situation against a practical list.

Who can make a separation agreement

A separation agreement is a type of domestic contract under the Family Law Act, alongside marriage contracts and cohabitation agreements. Two people who lived together and are now living separate and apart may make an agreement setting out their rights and obligations.

This applies to married and unmarried couples alike. Separation itself needs no court order, and it applies to married and common-law couples. Only married couples can divorce.

The formal checklist: writing, signatures and a witness

The Family Law Act says a domestic contract is unenforceable unless it is in writing, signed by the parties and witnessed. Sections 54 to 56 of the Act set out the basic requirements for a court to recognize and enforce a separation agreement.

• The agreement is in writing, not just a verbal understanding.
• Both parties have signed it.
• Each signature was witnessed.
• The parties were living separate and apart when they made it.

Understanding the terms and not being pressured to sign are different from these formal steps. They matter because, if those conditions are not met, the agreement can be challenged in court.

A template that is not properly signed and witnessed cannot be enforced. Filling in a template is only the start, because it still has to be signed and witnessed. Ontario does not require a lawyer to prepare the agreement.

Do you need a lawyer?

Ontario guidance says you do not need a lawyer to make a separation agreement. It also says legal advice before signing is a good idea, because it can be difficult to get a court to set an agreement aside. On property, the guidance adds that each spouse should have their own lawyer review the agreement before signing, and that the agreement cannot easily be changed later.

Sharing one lawyer is a particular problem. Before acting for more than one client, a lawyer must tell each of them that information received cannot be kept confidential from the others, and that the lawyer may have to withdraw from acting for everyone if a conflict develops that cannot be resolved. Ontario guidance recommends that separating spouses each have their own lawyer.

Disclosure, understanding and no pressure

A signed and witnessed agreement can still be challenged. A court may set aside a domestic contract, or a provision in it, if a party failed to disclose significant assets or significant debts that existed when the contract was made, if a party did not understand its nature or consequences, or otherwise in accordance with the law of contract.

Ontario guidance puts it simply: each person should understand the terms and not be pressured to sign, and if those conditions are not met the agreement can be challenged in court. The Court of Appeal for Ontario has called financial disclosure a paramount consideration, and has said the spouse who holds the assets is responsible for disclosing and valuing them.

• Financial disclosure means sharing information and documents about your income, expenses, assets and debts.
• Court financial statements are Form 13 for support-only cases and Form 13.1 where property or debts are in issue. Using the same kind of information is a sensible way to prepare before you sign.
• Even when one of the listed circumstances applies, the court then decides whether it is appropriate to set the agreement aside, and fairness is a relevant consideration.

Our separate article on setting aside a separation agreement in Ontario goes into this in more detail.

Mediated agreements and later changes

In family mediation, a neutral mediator helps you negotiate your own agreement, but does not make decisions, take sides or give legal advice. To make a mediated agreement legally binding, each party should get advice from a different lawyer before signing. The written result still has to be signed and witnessed like any other domestic contract.

If you later want to change the deal, an agreement to amend or rescind a domestic contract must also be in writing, signed by the parties and witnessed. Support terms can also be changed by a court order if circumstances change, for example a change in income or remarriage.

Finally, a signed agreement does not take away the court's power over children's issues. A court may disregard a provision about education, moral training, decision-making responsibility or parenting time if doing so is in the child's best interests. It may also disregard a child support provision that is unreasonable having regard to the child support guidelines. Our article on child support agreements in Ontario covers this further.

What to do next

• Gather income, tax, asset and debt records so that disclosure is complete before you negotiate.
• Read every term and ask about anything you do not understand before you sign.
• Arrange for each of you to get your own legal advice, rather than sharing one lawyer.
• Sign in front of a witness.
• Keep a fully signed copy of the agreement for each person.
• Write down any later change and have it signed and witnessed too.

If you are unsure whether your situation raises extra issues, such as pensions, support waivers or children's terms, a lawyer can review the agreement and confirm what applies to you.

Frequently asked questions