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Spousal Support Waiver Clauses in Ontario Marriage Contracts: What to Know

How spousal support waiver clauses work in Ontario marriage contracts, when courts respect them, and when they can later be challenged in court.

Family Law6 min readTSLBy the Treadstone Law team · OntarioUpdated 2026-07
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Key takeaways
  • A spousal support waiver clause is a term in a marriage contract in which one or both spouses give up, in advance, the right to claim spousal support from the other if the marriage ends.
  • People add a support waiver clause for a range of reasons: a significant income or asset gap going into the marriage, a second marriage where neither spouse wants an open-ended future…
  • A marriage contract is one of the domestic contracts recognized under the Family Law Act, along with cohabitation agreements and separation agreements.

You're drafting a marriage contract before the wedding, and one of you wants certainty: no spousal support, no matter what happens down the road. That request comes up in a large share of Ontario marriage contract negotiations, and it deserves more thought than a single line of boilerplate. A spousal support waiver clause can be part of a valid marriage contract in Ontario, but whether it actually holds up when a marriage ends depends heavily on how it was written and how the marriage played out.

Ontario's Family Law Act gives married spouses, and people planning to marry, real freedom to contract around the financial consequences of a future separation, including spousal support. Courts generally respect that freedom. They also keep a narrow ability to look past a waiver in specific situations, which is why a support waiver clause is best treated as a carefully built tool rather than a form you sign once and never think about again.

This guide walks through how a support waiver clause is typically drafted, what needs to be true for it to hold up, and where these clauses tend to get challenged later.

What a Support Waiver Clause Actually Does

A spousal support waiver clause is a term in a marriage contract in which one or both spouses give up, in advance, the right to claim spousal support from the other if the marriage ends. It can be:

A support waiver clause deals only with spousal support between the spouses. It cannot waive child support — child support belongs to the child, not to either parent, and a contract term trying to eliminate it isn't binding.

Why Couples Include One

People add a support waiver clause for a range of reasons: a significant income or asset gap going into the marriage, a second marriage where neither spouse wants an open-ended future support obligation, protecting a family business or professional practice from being treated as an income source for support, or simply wanting a predictable outcome instead of relying on a court's discretion years down the road. None of these reasons make a waiver automatically enforceable — they explain the motivation, not the legal effect.

What Makes the Clause Valid on Paper

A marriage contract is one of the domestic contracts recognized under the Family Law Act, along with cohabitation agreements and separation agreements. To be a validly signed domestic contract, it must be:

Ontario law doesn't require a court to approve a domestic contract before it's signed. That said, most family lawyers treat two extra steps as close to essential for a support waiver clause specifically to survive later scrutiny: each spouse getting independent legal advice before signing, and each spouse giving honest, reasonably complete financial disclosure to the other. Neither is a formality for validity in the strict sense, but both go directly to whether a court will later say each spouse actually understood what they were giving up.

Where a Court Can Still Step Around a Waiver

Signing a support waiver clause doesn't remove a court's ability to look at it later. Ontario courts keep a limited ability to override or disregard a spousal support waiver in circumstances such as:

It also helps to remember that spousal support was never automatic in the first place. Entitlement to spousal support has to be established on grounds such as need, compensation for economic disadvantage from the relationship, or an agreement between the spouses — the Spousal Support Advisory Guidelines are a widely used, non-binding tool for estimating amount and duration once entitlement exists, but they don't create entitlement on their own.

Signs a Waiver Clause Is Built to Last

Stronger waiver clausesWeaker waiver clauses
Full financial disclosure exchanged and attached as schedulesDisclosure vague, incomplete, or not documented
Each spouse had their own lawyer before signingOne lawyer drafted it for both, or nobody had advice
Signed with time to consider it, well before the weddingSigned hours before the ceremony under time pressure
Language is specific about what's being waived and whyBroad, one-line waiver with no context
Reviewed or updated after a major life changeNever revisited despite years of changed circumstances

Frequently asked questions

Can you waive spousal support entirely in an Ontario marriage contract?

You can include a clause attempting to waive it, and courts generally start from a position of respecting agreements spouses freely negotiated. But "entirely" isn't guaranteed — a court retains some ability to step around a waiver in specific circumstances, so treat it as a strong starting position, not an ironclad guarantee.

Does a support waiver need a lawyer to be legally valid?

The formal requirements for a valid domestic contract are that it's in writing, signed by both spouses, and witnessed — a lawyer isn't listed as a formal requirement. In practice, though, not having independent legal advice is one of the more common reasons a waiver gets challenged later.

What happens if we didn't fully disclose our finances before signing?

Incomplete financial disclosure is one of the clearest grounds a court can rely on to look past a support waiver. If either spouse's income, debts, or major assets weren't properly disclosed, the waiver is more vulnerable, even years later.

Can we add a support waiver after we're already married?

Yes — a marriage contract can be signed after the wedding, not just before it; some couples update or add one mid-marriage. The same formalities and enforceability considerations apply either way.

This article is general information, not legal advice. Reading it does not create a lawyer-client relationship. Ontario laws, tax rates, and government programs change, and how the law applies depends on your specific facts. For advice about your situation, speak with a licensed Ontario lawyer. Treadstone Law is licensed by the Law Society of Ontario — reach us at 1-844-900-1070 or start a file online.

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