Can a Marriage Contract Set Child Custody or Support in Ontario?

If you are expecting a child, or planning a family, you may wonder whether a prenuptial agreement can settle who gets the children and how much support will be paid if you separate. It is a sensible worry, and the short answer is that Ontario does not let parents decide these things in advance.

This article explains what a marriage contract can and cannot cover, why the law treats children differently, and what can be put in writing once a separation actually happens. It is general information and not legal advice.

What a marriage contract cannot decide

Ontario's government guidance is direct: marriage contracts and cohabitation agreements cannot say who has decision-making responsibility or parenting time for the children. You may hear older terms like custody and access. Today the focus is on decision-making responsibility and parenting time, and those are the matters a contract cannot settle.

Under the Divorce Act, a court making a parenting or contact order takes into consideration only the best interests of the child, giving primary consideration to the child's physical, emotional and psychological safety, security and well-being.

In practice, even if a prenup contained a clause about the children, a court would not simply follow it. It would look at what is best for the child when the question actually arises. Whether a particular clause has any effect is a question for a lawyer to confirm.

Child support is set by the guidelines

Child support follows the same logic. Under the Divorce Act, a child support order or interim order must follow the applicable guidelines, so child support is set by the court under the guidelines, not fixed by the parents' contract.

Child support also comes first when both child support and spousal support are in play. When a court considers both applications, it must give priority to child support. If that means no spousal support order or a lower one, the court must record its reasons, and a later reduction or end of child support is a change of circumstances for a spousal support application or variation.

This means a prenup that tries to fix child support in advance would not bind the court. What you can do is deal with child support properly once the family has separated and the real numbers and parenting arrangements are known.

What a marriage contract can still cover

Courts do look at agreements about spousal support. When making a spousal support order, a court must consider each spouse's condition, means, needs and other circumstances, including any order, agreement or arrangement relating to support of either spouse. So a support clause is not meaningless, but it is not the last word either. Our separate article on spousal support waivers goes into this.

What you can put in writing after separation

Ontario lists five kinds of domestic contract: marriage contracts, cohabitation agreements, paternity agreements, separation agreements and family arbitration agreements. A separation agreement is the usual document for parents who have separated and want to record their arrangements.

If support terms in a contract are to be enforced by the Family Responsibility Office, the contract must be filed with the Ontario Court of Justice or the Superior Court of Justice using form 26B, and then registered with the Family Responsibility Office. To change support terms, the parties must negotiate a new contract and file it with form 26B. The Family Responsibility Office cannot change the terms itself.

A marriage contract or cohabitation agreement must be signed by both spouses in front of a witness who also signs, and any later change must also be in writing and witnessed. For these contracts, Ontario's guidance also advises that each partner use a different lawyer and exchange financial information before signing. What is needed for a separation agreement to be valid is worth confirming with a lawyer.

What to do next

• Keep any prenup focused on property, support and who moves out, which are things a contract can cover.
• Do not rely on a clause about parenting time or decision-making; a court will look only at the child's best interests.
• If you separate, gather your income information, since child support is set under the guidelines.
• Consider recording your agreed arrangements in a separation agreement, and ask a lawyer what is needed for it to be valid.
• If you want the Family Responsibility Office to enforce support, ask a lawyer about filing the contract with form 26B.
• Speak with a family lawyer before signing anything that touches on children.

A lawyer can explain how these rules apply to your family and help you draft a contract that stays within what the law allows.

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