Changing or Challenging a Marriage Contract in Ontario?

When Might You Need to Change or Challenge a Marriage Contract?

Life Changes: Children, Career Shifts, Health Issues, or New Assets

Marriage contracts are often signed when couples first marry or begin cohabiting. At that time, they may not anticipate the significant changes that lie ahead—such as:

• Having children: Adding children to the family may alter priorities around property division or spousal support.
• Career changes: A spouse who once earned equally may now stay at home or earn significantly less, creating an imbalance.
• Health concerns: If one spouse develops a serious medical condition, prior terms may no longer reflect fairness or need.
• Accumulation of wealth or business growth: A spouse may have started a business or acquired substantial assets that weren’t anticipated at the time of signing.

Concerns over Fairness or One-Sided Terms

Sometimes, a spouse may wish to challenge the enforceability of a marriage contract if the terms appear heavily skewed in favour of the other. For example:

• A waiver of spousal support that leaves one party at a severe disadvantage
• Clauses that fail to acknowledge non-financial contributions to the marriage
• Provisions that ignore the reality of one spouse’s financial vulnerability

Canadian courts may set aside all or part of a contract if it results in an outcome that is “unconscionable” or clearly unfair under Ontario’s Family Law Act.

Discovering Missing Disclosure or Lack of Legal Advice at Signing

Full and honest financial disclosure is a cornerstone of any valid marriage contract. If it turns out that one spouse failed to disclose major assets or debts at the time of signing, the other may have grounds to challenge the contract.

Legal Grounds for Challenging a Marriage Contract in Ontario

Lack of Financial Disclosure

One of the most common reasons marriage contracts are challenged is due to incomplete or misleading financial disclosure at the time of signing. Under Ontario’s Family Law Act, each party must provide a full and honest account of their:

• Assets and liabilities
• Income and expenses
• Debts and obligations

If it is later revealed that one spouse withheld or misrepresented financial information, the court may find that the agreement was signed without informed consent—potentially rendering the contract invalid or unenforceable.

Absence of Independent Legal Advice

Courts place significant weight on whether both parties received independent legal advice (ILA) before signing a marriage contract. Legal counsel ensures that each party:

• Fully understands the implications of the agreement
• Is aware of their rights under Ontario family law
• Is not being unfairly pressured or misled

If a spouse signs a contract without ILA, a judge may be more inclined to scrutinise the terms and process. The lack of legal guidance can weaken the agreement’s enforceability—especially if the terms are later found to be one-sided.

Duress, Coercion, or Mental Incapacity at the Time of Signing

A marriage contract must be entered into voluntarily and by a party who is mentally capable of understanding its contents. The court may set aside a contract if it was signed under:

• Duress – threats or intense pressure, such as being forced to sign right before the wedding
• Coercion – undue influence from a more dominant spouse or family member
• Mental incapacity – lack of comprehension due to stress, illness, or impairment at the time of signing

Unconscionable or Grossly Unfair Terms

Even when a marriage contract appears valid on the surface, Ontario courts may still intervene if the terms are deemed unconscionable. This includes provisions that:

• Leave one spouse destitute while the other retains substantial wealth
• Completely waive spousal support without consideration for future changes (e.g., parenthood, disability)
• Ignore significant non-financial contributions to the marriage, such as caregiving or homemaking

How Ontario Courts Assess Validity of Marriage Contracts

Review of Circumstances at the Time the Contract Was Signed

Ontario courts look closely at what happened when the marriage contract was created, rather than just the consequences years later. The court considers:

• Whether full and honest financial disclosure was provided by both parties
• Timing of the agreement, particularly if it was signed shortly before the wedding, creating potential for undue pressure
• Independent legal advice (ILA) — Did each party understand the legal implications of the contract?
• Power dynamics and negotiation process, especially if one party had significantly more wealth, education, or bargaining leverage

If the agreement was signed under rushed or pressured circumstances, or without proper understanding, it may be considered procedurally unfair and subject to being set aside.

The Court’s Role in Protecting Vulnerable Spouses

Ontario courts are especially cautious when one spouse is in a weaker or more dependent position. This might include situations where a party:

• Had limited education or language skills
• Was financially dependent or inexperienced
• Signed under emotional stress or without understanding their rights

Even if the technical requirements were met (e.g., written form, ILA), a judge may intervene if the result is grossly unfair or unconscionable. The court’s role is to uphold fairness and equity, not just enforce agreements at face value.

Precedents from Key Ontario Family Law Cases

A number of landmark cases guide how courts in Ontario assess marriage contracts:

• LeVan v. LeVan (2008 ONCA 388): The Court of Appeal upheld a marriage contract due to proper legal advice and full disclosure, despite a significant disparity in wealth. The case clarified that the process of negotiation is key.
• Rosen v. Rosen (2004 CanLII 47720): This Ontario case highlighted that failure to disclose assets can be grounds to set aside a contract. The court ruled that accurate financial disclosure is a core component of enforceability.
• Virdee v. Virdee (2013 ONSC 6734): The court set aside a postnuptial agreement where the wife did not receive independent legal advice and signed under emotional strain. The court emphasized the importance of ILA and voluntariness.

The Process of Challenging a Marriage Contract

Filing an Application in Family Court

The first step in formally challenging a marriage contract is to file an application with the Ontario family court. This typically occurs within the context of a broader family law proceeding, such as:

• Divorce or separation proceedings
• A claim for spousal support
• A dispute over property division

In your court application (e.g., Form 8 or Form 8A under the Family Law Rules), you’ll need to state your intention to challenge the contract and the grounds for doing so, such as lack of disclosure or duress at the time of signing.

Gathering Evidence (e.g., Disclosure Documents, Legal Counsel Records)

To support your challenge, you will need to present compelling evidence. This may include:

• Financial disclosure documents: To show assets or debts that were hidden or omitted when the contract was signed
• Emails, letters, or texts: To demonstrate coercion, pressure, or lack of time to consider the agreement
• Independent legal advice records: Or lack thereof, to prove you signed without understanding your legal rights
• Witness testimony or affidavits: From legal professionals, family members, or financial experts

The more thorough your documentation, the stronger your position will be in court. Judges assess not only the content of the contract, but also the process by which it was created.

Possible Outcomes: Voiding the Agreement or Severing Certain Clauses

After reviewing the evidence and hearing both sides, the court may reach several possible conclusions:

1. Set aside the entire agreement – If the judge finds that the contract was fundamentally flawed (e.g., created under duress, lacked disclosure), it may be declared invalid in full.
2. Sever specific clauses – If only certain terms are unfair or unenforceable, such as a spousal support waiver, the court may void or rewrite those sections while upholding the rest.
3. Uphold the agreement – If the contract meets all legal requirements and the court sees no grounds to intervene, it will remain valid and enforceable.

Courts strive to respect autonomy while ensuring that contracts do not result in serious injustice or imbalance.

Steps to Modify an Existing Marriage Contract

Agreement from Both Parties Is Required

A marriage contract can only be modified if both spouses consent to the changes. One party cannot alter the agreement unilaterally, regardless of how much circumstances have changed. Mutual agreement is essential, and ideally:

• Discussions should be open, transparent, and without pressure
• Both spouses should understand the legal and financial consequences of the changes
• Each party should have the opportunity to receive independent legal advice to protect their interests

If agreement cannot be reached, mediation may help facilitate a resolution before turning to litigation.

Drafting an Amending Agreement or a New Contract

Once both parties agree to revise the terms, the next step is to formalize the changes in writing. There are two primary ways to do this:

1. Amending Agreement: This document modifies specific sections of the original contract while keeping the rest intact. It clearly states which clauses are being replaced or updated.
2. New Marriage Contract: In some cases, it may be more effective to revoke the old contract and replace it with an entirely new one. This approach helps eliminate confusion when numerous changes are involved.

Regardless of the method, the modified contract must:

• Be in writing
• Be signed by both spouses
• Be witnessed properly
• Comply with the requirements of Ontario’s Family Law Act

Failing to meet these formalities can lead to enforceability issues down the road.

Ensuring Updated Terms Reflect Current Laws and Financial Realities

The revised marriage contract should reflect your current financial situation, family structure, and Ontario law. This may include:

• Updated income, property values, or business assets
• New provisions for children or stepchildren
• Adjustments to spousal support based on earning capacity or health
• Clarifications to avoid ambiguity or misinterpretation

It’s also important to review legal developments that may impact the enforceability of certain clauses—such as spousal support waivers or asset exclusions.

Common Mistakes to Avoid When Updating or Challenging a Contract

Ignoring Legal Advice or Skipping Disclosure

One of the biggest pitfalls is failing to obtain independent legal advice (ILA) or provide full financial disclosure during the revision or challenge process.

• Lack of legal advice can lead to claims of unfairness, coercion, or misunderstanding—making the agreement vulnerable in court.
• Omitting financial details, such as debts, business interests, or pension plans, can invalidate parts or the entire contract.

Both spouses should fully understand the legal impact of the terms and have access to up-to-date financial information when making decisions.

Relying on Verbal Agreements or Side Letters

Modifying a marriage contract with oral agreements or informal side notes may feel convenient but carries serious legal risks.

• Verbal promises—even if made in good faith—are not legally binding under Ontario’s Family Law Act.
• Side letters or informal amendments may not meet the legal standards for enforceability.

To be valid, any changes must be in writing, signed by both parties, and witnessed. Courts will disregard informal arrangements that do not comply with these requirements, regardless of intent.

Failing to Properly Sign and Witness Changes

A marriage contract or any amendment to it must be executed correctly to be legally valid. Common procedural errors include:

• Missing or unqualified witness signatures
• Forgetting to date the amended agreement
• Only one spouse signing the revision
• Signing in separate locations without a witness present