Parents cannot use a relationship agreement to determine custody, support, or decision-making responsibilities in advance. These issues are decided by law if the couple separates, regardless of what their contract says.
Relationship agreements cannot lock in custody arrangements or parenting time schedules. Courts will always prioritize the best interests of the child at the time of separation, not the preferences expressed years earlier in a contract. Parenting needs change as children grow, and agreements made when a child is young may not fit the circumstances later on.
Child support is considered the right of the child, not the parents. This means parents cannot waive or set child support through a relationship agreement. The amount of support is determined based on federal or provincial guidelines that calculate payments according to income and parenting time.
Decision-making authority for important issues such as education, health care, and religion cannot be determined by contract. These responsibilities are allocated according to what is in the child’s best interests, either by agreement at the time of separation or by court order.
When parents separate, the process can either be managed with clarity and cooperation — or it can spiral into a contested, high-conflict divorce. Research shows that it’s not separation itself but the level of conflict between parents that most affects children’s well-being. The more uncertainty and fighting there is over money, property, and support, the harder it is for kids to adjust.That’s where relationship agreements — prenups, postnups, and cohabitation agreements — make a difference. By setting out how property, debt, and financial responsibilities will be handled if the relationship ends, these agreements give parents a roadmap. Instead of spending months or years fighting in court, families can move more quickly into a new routine.
Here’s how these agreements protect children from the fallout of separation:
A Canadian government review of research found that parental conflict before, during, and after separation is strongly linked to negative outcomes for children, including anxiety, depression, and behaviour problems. Children in high-conflict separations are at significantly greater risk. (Department of Justice Canada)
It is common for parents to want to acknowledge children in a relationship agreement. While binding custody and support terms cannot be included, parents sometimes add aspirational language. For example, they may state their shared intention to co-parent cooperatively, or to prioritize mediation before litigation.
These statements are not enforceable in the same way as financial provisions, but they can be helpful reminders of shared values. They also set a tone of cooperation that may influence how parents handle separation if it happens.
Children are also frequently mentioned in relationship agreements in the case of blended families. If one or both partners are bringing children into a new relationship, it’s common for couples to set out their expectations in terms of the role of the new partner in the child’s life. Some new partners wish to take on the role of a parent to their step-children, while others prefer to clarify that they will not step into the role of a full parent to their step-children. This can be useful for intention setting and clarity between partners, but it’s important to note that if a judge thinks that a step-parent has stepped into the role as a full parent, it’s possible that child support and custody could be ordered later on if it’s determined to be in the best interests of the child, regardless of what the relationship agreement says.
If parents separate, custody, parenting time, and support are addressed through family law processes. Relationship agreements may offer background context, but the enforceable decisions are made after separation either by agreement or through court order if parents cannot reach agreement on their own.
A parenting plan is a written agreement that outlines how parents will share responsibilities after separation. Parenting plans cover details such as where the child will live, how time will be shared between parents, how holidays will be divided, and how decisions about schooling or health care will be made. Parenting plans are flexible and can be tailored to the needs of each family. Courts will generally respect a parenting plan if it is reasonable and in the child’s best interests.
When parents cannot agree on a parenting plan, custody agreements or court orders are used to establish responsibilities. A custody agreement sets out legal custody (decision-making authority) and physical custody (where the child lives). The terminology and details may vary depending on the province, but the principle is the same: custody agreements focus on what is best for the child.
Custody agreements are directly enforceable in law. Parents can return to court if one person does not comply.
If you are a parent considering a relationship agreement, here are some practical points to keep in mind:
Relationship agreements are powerful tools for protecting couples and reducing conflict, but they are not substitutes for parenting plans or custody agreements. Parents who understand the distinction are better prepared to build agreements that are both enforceable and supportive of their children’s needs.
That’s why it’s essential to approach prenups thoughtfully, with fairness in mind. At Jointly, we make it easier to understand your options, learn about the law, and build agreements that protect your whole family – little ones included.
👉 Ready to explore your own agreement? Visit getjointly.ca to get started.
Aimee SchallesHi, I'm Aimee, a co-founder of Jointly. I’ve been working as a lawyer in British Columbia for over ten years. I run a small law firm and love helping people solve everyday problems. I’ve seen the difficulties that ordinary people face in accessing reliable legal services. I’ve also seen many friends and clients go through challenging separations that could have been improved if they’d have had a prenup or cohabitation agreement. I hope Jointly helps people make the relationship agreement they’ve been thinking about! Latest posts by Aimee Schalles (see all)