Cohabitation Agreements
Cohabitation Agreements (Common-Law “Prenups”)
Avoid a messy and expensive dispute over property, support, and finances by putting your agreement in writing before problems arise.
A cohabitation agreement lets you and your partner decide what is fair for your relationship, instead of leaving major issues to uncertainty, litigation risk, and whatever a court may later decide.
Take control before you need to
Common-law law in Canada can be surprisingly unclear, especially around property and finances. Many couples only discover the rules when they separate, and by then the conflict and legal fees have already started.
A cohabitation agreement is the practical way to create clarity now about what happens to the home; what happens to savings, debts, and investments; whether spousal support will be paid and on what terms; how you will divide (or not divide) assets if you separate; and how you will protect inheritances, businesses, or family property.
What is a cohabitation agreement?
A cohabitation agreement is a written domestic contract for unmarried couples who live together (or plan to). It can set out each partner’s rights and obligations if the relationship ends, whether by separation or death.
If you later marry, a cohabitation agreement continues in effect and functions like a marriage contract (often called a prenuptial agreement).
Why people get one
Couples usually come to us because they want clarity and a plan that matches their values, not a default legal outcome. Common goals include:
- Certainty and conflict prevention: clear rules reduce misunderstandings and disputes
- Protecting one partner’s career sacrifices: recognising time off work for parenting or caregiving
- Keeping a family business in the family: protecting shares, growth in value, and business assets
- Protecting inheritances and family gifts: keeping them outside any division arrangement
- Second relationships: ensuring children from a prior relationship are protected
- Unequal starting points: one partner owns more assets or has more debt going in
- Clear expectations: setting a tone of transparency and mutual understanding
When should you get a cohabitation agreement?
Ideally, before moving in together or before having children. That’s when everyone has the most leverage to be thoughtful, transparent, and fair.
That said, you can still make a cohabitation agreement after you are already living together; after you have children; after buying a property together; and any time you both want clarity and are willing to exchange financial information.
The sooner you do it, the easier it tends to be.
What can and can’t be included?
A cohabitation agreement is most useful for financial issues, especially:
Common topics you can cover
You can cover ownership and division of property (including the home); how joint purchases will be treated; treatment of debts (existing and future); spousal support (waiver, lump sum, periodic support, or a formula); treatment of inheritances, gifts, and excluded property; businesses, and their growth in value; and what happens on death (often coordinated with wills/beneficiary designations).
Important limits (especially about children)
Parents can express intentions about parenting, but the law prioritises children’s best interests and child support must reflect legal requirements. In practice: child support cannot be finally “contracted out of”; and parenting terms may not be enforceable if they conflict with a child’s best interests or later circumstances.
A well-drafted agreement can still be helpful by setting expectations and reducing conflict, but it should be written with these limits in mind.
Clauses that usually don’t help
Courts are generally skeptical of “moral” clauses (for example, financial penalties tied to infidelity). They tend to create litigation rather than prevent it.
Are cohabitation agreements legally valid?
Yes, when properly prepared and signed, they are generally enforceable. But courts scrutinise domestic contracts more closely than ordinary commercial contracts. The biggest enforceability risks usually come from:
- Pressure or unfair process (duress)
If one partner is pressured, rushed, or presented with a sign or else situation, the agreement is at risk. - Incomplete financial disclosure
If one partner does not provide full and honest disclosure of assets, debts, and income, the agreement may be set aside or reworked by a court. - Bad drafting or improper signing formalities
Domestic contracts must be in writing and properly signed and witnessed. Sloppy execution creates avoidable risk. - Unconscionability or extreme unfairness
Even with disclosure and formalities, a court may refuse to enforce a provision that is grossly unfair in the circumstances.
A strong agreement is not just about the final terms. It is also about a fair process and clean documentation.
What happens if we marry?
In most cases, a properly drafted cohabitation agreement continues to be effective after marriage, functioning like a marriage contract.
Our flat fee
We offer a flat fee so you know the cost up front.
If you and your partner are broadly in agreement on the major terms, our fee for a cohabitation agreement is $1,700 + HST.
Flat-fee arrangements work best when both parties are prepared to exchange financial disclosure and negotiate in good faith. If the issues are unusually complex (business interests, significant assets, multiple properties, or significant negotiation), we will tell you early if the work is likely to fall outside a typical flat-fee file.
What the process typically looks like
- Intake and goals: what you want to protect and what “fair” looks like for you
- Financial disclosure: both partners exchange clear, written disclosure
- Drafting: we prepare a draft agreement tailored to your situation
- Review and revisions: we refine the terms based on your feedback
- Signing properly: signatures and witnessing are completed correctly
- Independent legal advice: your partner should obtain independent legal advice from their own lawyer
Independent legal advice is not just a formality. It materially strengthens enforceability.
Get started
To get started, call 613-402-0000 or use the contact form on this website.
