Marriage & Cohabitation Agreements in Ontario
Planning ahead is one of the most thoughtful things a couple can do for each other.
A marriage contract, commonly called a prenuptial agreement, and a cohabitation agreement are not signs of distrust. They are signs of clarity. They allow couples to make deliberate, informed decisions about their financial arrangements at a time when they are thinking clearly and working together, rather than leaving those decisions to legislation written for strangers, or to a negotiation happening in the aftermath of separation.
Megan helps couples approach these conversations constructively, with respect for both parties and a focus on what is actually fair and workable for their specific situation.
Marriage contracts (prenuptial agreements)
A marriage contract is a domestic contract entered into by two people who are married or intend to marry. Under Ontario's Family Law Act, a valid marriage contract can:
Alter or exclude the equalization of net family property
Address spousal support — including waiving it entirely, capping it, or setting out agreed terms
Specify what happens to specific assets if the marriage ends
Protect pre-marriage assets, inheritances, or family gifts
Address property rights and financial arrangements during the marriage itself
What a marriage contract cannot do:
A marriage contract cannot affect parenting arrangements or child support for children not yet born at the time the contract is signed. The rights of the children always take precedence over the contractual arrangements of the parents.
Cohabitation agreements
A cohabitation agreement is for couples who are living together or planning to live together outside of marriage. It operates similarly to a marriage contract but applies to common-law relationships.
This is particularly important in Ontario because common-law partners do not have the same property rights as married spouses under the Family Law Act. There is no automatic equalization for common-law couples. Without an agreement, property disputes between common-law partners are resolved through general legal principles, unjust enrichment, constructive trust, which are far less predictable and far more expensive to litigate.
A cohabitation agreement can define clearly what each partner owns, how shared property will be handled, whether spousal support applies, and how finances will be managed during the relationship.
Note: If a couple with a cohabitation agreement later marries, the agreement automatically becomes a marriage contract, unless the agreement says
Why couples get these agreements
There is no single profile of a couple who benefits from a domestic contract. Common situations include:
Second marriages or relationships — where one or both partners have assets, property, or children from a previous relationship that they want to protect or keep separate.
Significant financial imbalance — where one partner enters the relationship with substantially more assets, an inheritance, or a business interest, and both parties agree that it is fair to keep that property separate.
Family property or business interests — where one partner owns an interest in a family business, inherited property, or other assets with sentimental or financial significance to their family of origin.
Partners who simply want clarity — couples who want to define their financial arrangements proactively rather than leaving them to the default rules of the Family Law Act.
What makes a domestic contract enforceable?
For a marriage contract or cohabitation agreement to be legally binding in Ontario:
It must be in writing
It must be signed by both parties
It must be dated
Each signature must be witnessed
Both parties must have provided full financial disclosure
Both parties must have had an opportunity to obtain independent legal advice
The last two points are the most important from an enforceability standpoint. Agreements entered into without full disclosure or without independent legal advice are significantly more vulnerable to being set aside later.
This is why Megan strongly recommends, and actively facilitates, that both parties obtain independent legal advice before signing. It protects both of you.
Domestic contracts and independent legal advice
If you and your partner have already negotiated the terms of a cohabitation agreement or marriage contract and are looking for a lawyer to review it with you before signing, that service is called Independent Legal Advice (ILA). Megan provides ILA as a standalone service.
A note on difficult conversations
The conversation about a marriage contract or cohabitation agreement can feel awkward, even for couples with the best intentions. Megan has had this conversation with many clients and brings both legal clarity and genuine sensitivity to it.
The goal is not to plan for failure. It is to ensure that if something changes, both people are protected. That is a form of care, not suspicion.