Can You Sign a Marriage Contract After the Wedding in Ontario?

You are married, and you never signed a prenup. Now you wonder whether it is too late to put your financial arrangements in writing. People often search for a postnuptial agreement in Ontario because they want clarity about property, support or what happens if the marriage ends.

The short answer is that Ontario law allows it, though it uses different words. This article explains what the law calls these agreements, what they can and cannot cover, how to make one valid, and where a court can still step in.

What Ontario calls a postnuptial agreement

Ontario's Family Law Act does not use the words prenup or prenuptial agreement. Those are informal names. The Act uses the term marriage contract. A marriage contract is one kind of domestic contract, along with separation agreements, cohabitation agreements, paternity agreements and family arbitration agreements.

A marriage contract is not limited to the time before the wedding. Two people who are married to each other, or who intend to marry, may make one. So what many people call a postnuptial agreement is, in Ontario law, a marriage contract signed after the wedding.

What it can and cannot cover

In a marriage contract, spouses can agree on their rights and obligations during the marriage, on separation, on annulment or dissolution of the marriage, or on death. It may deal with ownership or division of property, support obligations, and any other matter in the settlement of the couple's affairs.

There are limits:

• It cannot deal with decision-making responsibility or parenting time for children, although it may deal with the right to direct their education and moral training.
• A term that tries to limit a spouse's rights in the matrimonial home under Part II of the Act is unenforceable. That includes the equal right to possess the home, whoever owns it.
• A term that ends a party's rights on separation because that party is not chaste is unenforceable, while a term ending rights on marriage or cohabitation with another person is still given effect.
• Dividing a pension by contract is restricted, although a contract may provide for an immediate transfer of a lump sum out of a pension plan.

Why spouses sign one: the default rules

Without a contract, the Act's equalization rules apply. Net family property is the value of what a spouse owns on the valuation date, except excluded property, after deducting debts and liabilities and the value of property, other than a matrimonial home, owned on the date of marriage. On divorce, nullity or separation with no reasonable prospect of resuming cohabitation, the spouse with the lesser net family property is entitled to one-half of the difference.

A contract can change this. Property the spouses agree by domestic contract is not to be included is excluded from net family property. This matters, for example, for a matrimonial home owned before the marriage. Without a contract, its full value must be shared unless the spouses agree otherwise. A contract that is valid is generally given priority where it deals with a matter the Act also covers, unless the Act provides otherwise.

Making it valid, and when a court can set it aside

A domestic contract, and any agreement to amend or rescind one, is unenforceable unless it is in writing, signed by the parties and witnessed. Both spouses sign in front of a witness, and the witness also signs. Special rules apply if a spouse is a minor or mentally incapable.

None of those formal requirements involves a lawyer. Still, Ontario's government advises that each partner speak to a different lawyer and that the partners exchange financial information before signing.

Even a properly signed contract can be challenged. On application, a court may set aside a contract or a provision in it on these grounds:

• A party failed to disclose significant assets, or significant debts or other liabilities, existing when the contract was made.
• A party did not understand the nature or consequences of the contract.
• Otherwise in accordance with the law of contract, which is the route for arguments such as duress or pressure to sign.

A clause saying the contract cannot be challenged does not remove this power.

Children and support: where the court can override

So a support waiver in a contract signed after the wedding is not automatically final. Spouses who divorce should also know that under the Divorce Act a court deciding spousal support considers any agreement as a factor, not a bar to support.

What to do next

• List all your assets and debts, and share them with your spouse before signing.
• Decide what you want to cover: property, support, the home, death.
• Each speak to a different lawyer before you sign.
• Sign in writing, both spouses, in front of a witness who also signs.
• Keep a signed copy somewhere safe, and put any later change in writing too.

If you are unmarried, a cohabitation agreement is the equivalent, and it is deemed to be a marriage contract if you later marry each other. Because the right terms depend on your property, family and goals, a lawyer can confirm how the rules apply to you.

Frequently asked questions