Marriage Contracts and Cohabitation Agreements in Ontario

Ontario's Family Law Act allows domestic contracts: marriage contracts (for married or soon-to-be-married couples) and cohabitation agreements (for couples living together).

Formal requirements

Under section 55 of the Family Law Act, a domestic contract must be:

• in writing;
• signed by both parties; and
• witnessed.

What it can cover

• Ownership and division of property
• Spousal support
• Other matters in the relationship

Limits

• Terms about children's custody and parenting can be set aside if not in the child's best interests.
• A marriage contract can't limit a spouse's rights to possession of the matrimonial home.

When courts set them aside

• One person didn't disclose significant assets or debts.
• One person didn't understand the nature or consequences of the contract.
• Other contract law grounds, such as duress.

Independent legal advice

Each person should have their own lawyer review the contract. It makes the agreement much harder to challenge.

Getting help

Family law is outside a paralegal's licence. NEO can refer you to a family lawyer and commission documents.

Sources

• Family Law Act (Ontario)
• Ontario: dividing property when a relationship ends

Read next: Getting Married in Ontario: The Marriage Licence and Ceremony

General Ontario legal information, not legal advice for your matter, and reading it does not create a retainer. Sources checked 16 October 2026: check the current law, forms and dates before you act.

Photos from Unsplash: Person pointing at a marriage certificate on a wooden table · Couple signing wedding papers with guests watching.

This article is general information for people in Ontario, not legal advice. Rules, forms and deadlines change, and every situation is different. Check the current rule or speak to a licensed legal professional before you act.