Can a cohabitation agreement deal with who keeps the pets if we separate in Ontario?

Yes. Pets can be addressed in a cohabitation agreement, and doing so is increasingly common. Under Ontario law, pets are legally treated as personal property — they are not treated like children for the purposes of family law, and there is no statutory "best interests of the animal" test the way there is for children. This means that if a couple cannot agree on who keeps the pet, the legal default is that whoever has legal ownership or paid for the animal retains it, which may not reflect the relationship each person has with the pet.

A cohabitation agreement can specify who will have primary care of a pet if the relationship ends, how shared custody of a pet might work if both partners want ongoing time with the animal, and who is financially responsible for veterinary and care costs during and after the relationship. Courts are not obligated to enforce pet custody arrangements the way they enforce child parenting schedules, but a written agreement that both parties signed is a strong starting point for resolving disagreements.

If the couple has a deeply beloved pet and both have a strong attachment, addressing this upfront — even briefly — prevents it from becoming a contested and emotionally charged issue at separation.