Cohabitation agreements are a valuable tool for unmarried couples who want to protect their rights and outline how finances, property, and responsibilities will be handled during and after their relationship. But what happens when an agreement no longer feels fair, or one partner questions its validity? Can a cohabitation agreement be voided?
In short, yes, under specific circumstances. But voiding a cohabitation agreement in Ontario (or elsewhere in Canada) isn’t as simple as changing your mind. The courts take these contracts seriously, especially when they’re drafted properly. However, certain legal flaws or unfair conditions can render an agreement unenforceable.
This guide explains when and how a cohabitation agreement can be voided, what red flags to watch for, and how to protect yourself, whether you’re entering into an agreement or considering contesting one.
Cohabitation agreements are private legal contracts between two unmarried partners who live, or plan to live, together. While courts generally uphold these contracts, they can be voided (declared legally unenforceable) in specific situations. Grounds for voiding a cohabitation agreement include:
To void an agreement, you must apply to the court and prove that it meets one or more of these criteria.
Ontario courts (and those in other provinces) have invalidated cohabitation agreements in cases where:
These are not merely technicalities; they speak to the integrity and fairness of the agreement, which is what courts will scrutinize.
In both prenuptial and cohabitation agreements, full financial disclosure is critical. Courts in Ontario have ruled that hiding assets, undervaluing property, or failing to disclose debts can be grounds to void an agreement.
Without a clear picture of each person’s finances, a partner may agree to terms they wouldn’t have otherwise accepted. This undermines the concept of informed consent and makes the agreement vulnerable to challenge.
Courts won’t uphold agreements signed under pressure. This includes:
Even subtle forms of pressure can tip the scales. If one partner felt they had no real choice other than signing the agreement, a judge may decide the agreement wasn’t truly voluntary.
If an agreement heavily favors one partner at the expense of the other, the court may find it unconscionable. For example:
While courts respect private agreements, they won’t enforce contracts that are fundamentally unjust. If one partner will be left destitute while the other is comfortable, it’s unlikely that a court would view that agreement as fair.
To void a cohabitation agreement, the process typically involves:
It’s important to note that courts don’t void agreements lightly. The burden of proof falls on the person contesting the agreement.
If you believe your agreement should be voided, consult a family law lawyer early. A lawyer can help you:
They may also explore whether the agreement can be amended instead of voided entirely. It is possible to represent yourself in court, but it can be a highly challenging and technical process. If you can afford to hire a lawyer to help you, it is extremely beneficial.
When an agreement is voided, default provincial laws apply. In Ontario, for common law couples, this may mean:
In essence, voiding the agreement means the protections and boundaries it created are removed.
If a couple reconciles after signing, or after beginning to challenge, an agreement, the agreement may still be valid. However, if both parties acted as though the agreement no longer applied, a court might view it as abandoned or modified by conduct.
It’s important to be consistent: if you continue to rely on the agreement, update it. If you’ve changed course, make those changes official. A cohabitation agreement is a document you should revisit regularly throughout your relationship.
The best way to avoid issues later is to get the agreement right from the start. That means:
A well-drafted agreement helps prevent future disputes and protects both partners—whether they stay together or not.
Sometimes an agreement feels outdated, not unfair. If circumstances have changed (e.g. kids, income changes, or long-term caregiving), it may be better to amend the agreement instead of voiding it.
Amending allows you to:
Voidance, on the other hand, wipes the agreement off the table entirely. You can then rely on provincial law, or create a new agreement.
To amend an agreement:
To dissolve an agreement without the agreement of both partners, you’ll need a court order.
Family law varies by province. In Ontario, common law couples do not automatically share property even if they’ve lived together for many years.
A cohabitation agreement in Ontario can override this by granting property rights, spousal support, or inheritance rights that wouldn’t otherwise exist.
In British Columbia, the rules are different: common law partners who’ve lived together for two years have similar property rights as married spouses. This means the impact of voiding an agreement can differ depending on where you live.
A cohabitation agreement is often the only legal protection for unmarried partners. Voiding one removes those protections. That’s why it’s essential to:
Our Agreement Starter Kit will take you through everything you need to know about family law in your province.
A cohabitation agreement outlines how an unmarried couple will handle:
It’s a form of relationship planning that provides clarity and reduces conflict similar to a prenuptial agreement, but tailored to common law couples.
Without a cohabitation agreement, common law partners in Ontario are not entitled to equal division of property, even after decades together. This means one person may leave the relationship with nothing unless they can prove a claim like unjust enrichment.
A cohabitation agreement gives both partners security, transparency, and peace of mind. Cohabitation agreements are useful for everyone, but they’re especially important when:
At Jointly, we make creating a legally sound cohabitation agreement easy, accessible, and affordable without the stress or intimidation of traditional legal processes.
Here’s what sets us apart:
✅ Designed for Canadian couples – Our platform is built with the legal requirements of Canadians in mind.
✅ User-friendly – Step-by-step guidance helps you create a clear, enforceable agreement without legal jargon.
✅ Collaborative and transparent – Work together with your partner from start to finish.
✅ Amendments made simple – As your relationship evolves, your agreement can too. We offer lifetime access to our platform so you can make changes that reflect your life together.
Whether you’re drafting your first agreement or looking to revise an outdated one, Jointly empowers you to protect what matters most together.
Ready to take control of your future?
Get started with your cohabitation agreement today.