Living together without marrying is common in Alberta. What many couples do not realize is that moving in together can create legal and financial obligations — and that separating can be as complicated as a divorce. A cohabitation agreement lets you decide those terms in advance, rather than being governed by default rules. Here is why it matters, what it should cover, and what you risk without one.

What Is a Cohabitation Agreement?

A cohabitation agreement is a written contract between two people who live together, or plan to, that sets out how they will handle property, debts, finances, and support during the relationship and if it ends. In Alberta, it is a type of family property agreement that lets partners “opt out” of the default division rules the law would otherwise apply.

Alberta’s family laws are built around the “adult interdependent partner”. You generally become an adult interdependent partner once you have lived together in a relationship of interdependence for at least three continuous years. However this designation can apply sooner if you have a child together and your relationship is one of some permanence, or immediately if you sign a formal adult interdependent partner agreement.

Why Couples Should Consider a Cohabitation Agreement

Protecting property and assets. Since 2020, Alberta’s Family Property Act applies to adult interdependent partners the same way it applies to married spouses. On separation, property that either partner acquired after the relationship began is presumed to be divided equally, unless a court decides otherwise. An agreement lets you keep a home, savings, or assets you obtained during the relationship, rather than leaving these to be governed by the default rules.

Defining financial responsibilities during the relationship. An agreement is not only about separation. It can record who pays for what, how you share household costs, and how you treat joint purchases and accounts — reducing day-to-day friction and misunderstanding.

Reducing conflict if you separate. When the law has to sort out your affairs after a breakup, a court weighs a long list of factors including each partner’s contributions, the length of the relationship, each person’s finances, and more. That process is uncertain, slow, and expensive. A clear agreement settles most of these questions ahead of time, so a separation does not become litigation.

Protecting inheritance and family business interests. Gifts, inheritances, and property you owned before the relationship are generally exempt from division but any increase in their value during the relationship can still be shared, and tracing what is exempt years later is often contentious. If you have a family business, a stake you want to keep in the family, or an inheritance you expect to receive, an agreement can confirm it stays yours and spare your partner and your relatives from conflict.

Key Elements to Include in a Cohabitation Agreement

Division of property and debts. Identify what each of you brings in, what will stay separate, and how property and debts acquired during the relationship will be divided if you separate. This is the core of opting out of the Family Property Act’s equal-division presumption.

Spousal (partner) support expectations. Adult interdependent partners can apply for partner support on separation, assessed on factors such as the length of the relationship and each person’s needs and means.  You can address whether support will be paid, waived, or limited — though, as noted later on, support terms get separate scrutiny.

Household expenses and joint accounts. Set out how you split rent or mortgage, bills, and shared expenses, and how joint accounts and jointly owned items are handled.

Children from previous relationships. You can clarify financial arrangements and how shared assets are protected for children from a prior relationship. However, an agreement cannot bind a court on child support or parenting for the children themselves as those are decided in the child’s best interests, not by contract.

When Should You Get a Cohabitation Agreement in Alberta?

Before moving in together. This is the ideal time. You can set expectations calmly, before finances are entangled and before the three-year clock that creates adult interdependent partner status has run 

After cohabitation begins. It is not too late once you have moved in. Couples regularly sign agreements years into a relationship — before buying a home, starting a business, or receiving an inheritance. An agreement entered during the relationship is equally valid if it meets the legal requirements.

The longer you wait, the more property accumulates and intermingles, and once you cross into adult interdependent partner status the Family Property Act’s division rules apply by default. Waiting until a relationship is in trouble is the worst option: agreements negotiated in the turmoil of a breakdown draw far more suspicion from courts, which are wary of unequal deals struck under pressure.

Common Myths and Misconceptions

“We don’t need it because we trust each other.” Trust is not the point. An agreement is not a sign of doubt — it is clarity. It records what you both intend while you agree, so that a future disagreement, or a court applying generic default rules, does not decide for you.

“It’s only for the wealthy.” Not so. The default property and support rules apply to ordinary couples with a home, a vehicle, savings, and debts — exactly the assets most people fight over. An agreement protects modest estates just as much as large ones.

“It means we’re planning to break up.” No more than insurance means you are planning a fire. An agreement is a practical safeguard that, in most cases, is signed and never needed. It can actually strengthen a relationship by removing financial uncertainty.

What Happens Without a Cohabitation Agreement?

Without an agreement, Alberta’s default rules decide for you. If you qualify as adult interdependent partners and separate, either of you can ask a court to divide the property acquired during the relationship equally and to order partner support based on the statutory factors and objectives. You lose control over the outcome, and resolving it can mean months of negotiation or court proceedings.

Effective Cohabitation Agreements

To be effective, a cohabitation agreement must be done properly. For the property terms, Alberta law requires that each partner acknowledge in writing, and separately from the other, that they understand the agreement’s nature and effect, know the property claims they are giving up, and are signing freely and voluntarily — and that acknowledgment must be made before a lawyer who is not acting for the other partner. These formalities exist so that opting out of equal division reflects free and informed consent; an agreement that ignores them may be given little weight by a court.

Support terms are scrutinized separately. A waiver of partner support is tested for fairness, and a court can set it aside or order support anyway — especially where a partner did not get independent legal advice or the terms are unfair in the circumstances. By contrast, a mutual waiver made with independent advice and proper acknowledgments on both sides is far more likely to hold up. 

Conclusion

Cohabiting couples in Alberta carry many of the same legal and financial obligations as married spouses, often without realizing it. A cohabitation agreement puts the key decisions — how property and debts are divided, how finances are shared, and whether partner support will apply — in your hands rather than leaving them to default rules and a court’s discretion. Having an agreement in place can protect assets each of you brought into the relationship, reduce conflict, and most importantly, give both partners certainty. It is not a sign of distrust or a plan to separate; it is simply wise planning for couples at any income level. To be sure your agreement holds up, each partner should get independent legal advice and the required written acknowledgments. The best time to put a cohabitation agreement in place is before you move in but it is never too late to protect yourself and your partner.