A Canadian Roommate Agreement is a private contract between co-tenants or between a primary tenant and a subtenant who share a rental unit. It governs the internal financial and household arrangements between the roommates — rent splitting, utility costs, common area responsibilities, guest policies, and departure procedures — without replacing or modifying the primary lease between the landlord and the tenant(s) listed on that lease.

This agreement operates in a specific legal gap. Provincial residential tenancy legislation — Ontario's Residential Tenancies Act, 2006 (S.O. 2006, c. 17), BC's Residential Tenancy Act (S.B.C. 2002, c. 78), Alberta's Residential Tenancies Act (S.A. 2004, c. R-17.1) — governs the relationship between a landlord and a tenant, but it does not regulate the relationship between roommates sharing the same unit. The Landlord and Tenant Board (Ontario), Residential Tenancy Branch (BC), or equivalent provincial tribunal has no jurisdiction over roommate-to-roommate disputes. A roommate agreement is therefore a common law contract enforceable through the provincial small claims court.

A critical distinction is whether a roommate is a co-tenant on the primary lease or an occupant who has no direct relationship with the landlord. Co-tenants are jointly and severally liable for the full rent — if one roommate stops paying, the others must cover the shortfall or the entire tenancy is at risk. An occupant who is not on the lease has no direct obligation to the landlord but may be bound by the roommate agreement to contribute to rent and expenses.

Security deposit rules vary significantly by province and affect roommate arrangements. Ontario prohibits security deposits entirely (only last month's rent deposits are permitted under the RTA). BC allows a damage deposit of up to half a month's rent. Alberta allows a security deposit of up to one month's rent. Quebec prohibits security deposits altogether. These provincial rules apply to the landlord-tenant deposit, but the roommate agreement may establish a separate deposit between roommates for shared furnishings or common area damages.

When two or more individuals are moving into a shared rental unit and need to establish clear financial responsibilities before the first rent payment is due — defining each person's share of rent, how utilities are divided, and who is responsible for paying the landlord and collecting from the others.

When a primary tenant who is on the lease wants to bring in a roommate who will not be added to the lease, and both parties need a written agreement governing the occupant's financial obligations, house rules, and the process for terminating the arrangement with appropriate notice.

When university or college students are sharing off-campus housing and need a structured agreement covering quiet hours during exam periods, cleaning schedules, kitchen usage, shared grocery arrangements, and the procedure if one student wants to move out before the lease term ends.

When roommates have unequal living arrangements — one occupying the master bedroom with an en-suite bathroom and the other in a smaller room with a shared bathroom — and the rent split must reflect the difference in space and amenities rather than defaulting to an equal division.

When an existing roommate arrangement has been operating informally and a new roommate is being added or an existing roommate is departing, requiring documentation of the transition, the new cost allocation, and the departing roommate's obligations for their share of any outstanding bills or damages.

Without a roommate agreement, disputes over unpaid rent shares, utility bills, cleaning responsibilities, or damage to shared spaces have no documented resolution framework and must be pursued through small claims court based on oral testimony and bank transfer records alone.

Rent Allocation — Each roommate's specific share of the total monthly rent, the method of calculation (equal split, proportional based on room size, or a custom amount), the due date each month, and who is responsible for making the payment to the landlord. If one roommate collects and pays the landlord, establish that person's obligation to provide receipts or confirmation of payment.

Utility and Expense Sharing — How electricity, gas, water, internet, and cable costs are divided. Specify whether the split is equal or proportional, which roommate's name each utility account is under, and the deadline for reimbursing the account holder. Address shared household supplies (cleaning products, toilet paper, kitchen basics) and whether a shared fund is maintained.

Security Deposit Between Roommates — Any deposit the incoming roommate pays to the existing tenant or co-tenants for shared furnishings, appliances, or common area condition. This is separate from the landlord's deposit and is governed by the roommate agreement, not the provincial tenancy act. Specify the amount, what it covers, and the conditions for return upon departure.

Common Area Responsibilities — A cleaning schedule or rotation for shared spaces (kitchen, bathroom, living room, hallways). Define standards for cleanliness, dishwashing timelines, garbage and recycling duties, and snow removal or yard maintenance if applicable.

Guest and Overnight Visitor Policy — Rules regarding guests, including overnight visitors, extended stays (typically more than three consecutive nights), and any restrictions on guests using shared facilities. This is one of the most common sources of roommate conflict and should be addressed explicitly.

Quiet Hours and Noise — Defined quiet hours (commonly 10 PM to 8 AM on weekdays, midnight to 9 AM on weekends), restrictions on loud music or instruments, and expectations for noise levels during study or work-from-home periods.

Pet Policy — Whether pets are permitted (subject to the primary lease and applicable provincial law), which roommate is responsible for pet care and any pet-related damage, and any restrictions on the type, size, or number of animals.

Early Departure and Notice — The notice period required if a roommate wants to move out before the lease ends (typically 30 to 60 days), the departing roommate's obligation to continue paying their rent share until a replacement is found or the notice period expires, and who is responsible for finding a replacement roommate.

Dispute Resolution — A process for resolving disagreements between roommates, typically starting with a house meeting and escalating to informal mediation before resorting to small claims court. Specify the governing province whose laws apply to the agreement.