A Canadian Sublease Agreement is a contract between an existing tenant (the sublessor) and a new occupant (the sublessee or subtenant) that grants the subtenant the right to occupy all or part of the rental unit for a specified period, while the original tenant retains their obligations under the primary lease with the landlord. The sublease creates a secondary tenancy relationship layered on top of the original lease — the sublessor becomes both a tenant (to the landlord) and a landlord (to the subtenant).

Provincial residential tenancy legislation governs subleasing rights and requirements. Under Ontario's Residential Tenancies Act, 2006 (s. 97), a tenant may sublet the rental unit with the landlord's consent, and the landlord cannot unreasonably withhold consent. If the landlord refuses consent without reasonable grounds, the tenant may apply to the Landlord and Tenant Board (LTB) for an order permitting the sublease. BC's Residential Tenancy Act (s. 34) similarly requires the landlord's written consent, which cannot be unreasonably withheld. Alberta's Residential Tenancies Act requires consent unless the lease expressly prohibits subletting. Quebec's Civil Code (art. 1870-1873 C.C.Q.) uniquely allows tenants to sublet without the landlord's consent, though the landlord must be given notice and may refuse only for serious reasons.

A critical legal distinction exists between a sublease and an assignment. In a sublease, the original tenant retains responsibility under the primary lease and the subtenant occupies for a period shorter than the remaining lease term. In an assignment, the original tenant transfers the entire remaining interest to the new tenant, who steps into the original tenant's position. This distinction determines which party the landlord can pursue for rent arrears and property damage — in a sublease, the original tenant remains fully liable to the landlord for any default by the subtenant.

Rent restrictions apply in several provinces. Under Ontario's RTA (s. 134), the sublessor cannot charge the subtenant more than the lawful rent under the primary lease. This prevents profit-taking through subleasing and protects subtenants from being charged inflated rents. BC and Alberta do not have equivalent statutory restrictions on sublease rent, though the landlord's consent conditions may address this.

When a tenant needs to vacate their rental unit temporarily — for work relocation, extended travel, academic exchange, or a temporary assignment — and wants to maintain the tenancy by subletting to a subtenant rather than breaking the lease and losing the unit.

When a tenant in a rent-controlled apartment in Ontario wants to preserve their below-market rent by subletting during an absence rather than terminating the lease, since the sublessor has the right to resume occupancy at the end of the sublease term and the landlord cannot raise the rent above the guideline amount.

When a commercial tenant needs to sublet a portion of their leased premises — one office, a section of a retail space, or a shared co-working area — to offset rent costs while remaining on the primary lease and retaining the right to expand back into the space.

When a university student wants to sublet their apartment during the summer break and needs a formal agreement with the subtenant covering the rent amount, the condition of the unit, the use of furnishings, and the subtenant's obligation to comply with the building rules and the primary lease terms.

When a tenant is considering a permanent relocation but is unsure whether they want to give up the unit, and a sublease provides a trial period during which they can evaluate the new situation while keeping the option to return.

Without a sublease agreement, the original tenant has no contractual recourse against the subtenant for unpaid rent, property damage, or violations of the building rules — and remains fully liable to the landlord for everything that happens during the subtenant's occupancy.

Landlord Consent — Evidence that the landlord has provided written consent to the sublease as required by the applicable provincial tenancy act. In Ontario, the landlord cannot unreasonably withhold consent (RTA s. 97). In BC, written consent is required (RTA s. 34). In Quebec, no consent is needed but the landlord must be notified (C.C.Q. art. 1870). Attach the landlord's consent letter as a schedule to the sublease.

Primary Lease Incorporation — A clause incorporating the terms of the primary lease by reference and obligating the subtenant to comply with all terms that apply to the use and occupation of the unit. The subtenant should receive a copy of the primary lease. Any term in the sublease that conflicts with the primary lease is generally unenforceable.

Sublease Term — The start and end dates of the sublease, which must fall within the remaining term of the primary lease. In a true sublease, the sublessor retains at least one day of the primary lease term — if the entire remaining term is transferred, the transaction is an assignment, not a sublease, and different legal consequences apply.

Rent and Payment — The monthly rent payable by the subtenant, the due date, and the payment method. In Ontario, the sublease rent cannot exceed the lawful rent under the primary lease (RTA s. 134). Specify whether the subtenant pays the sublessor (who then pays the landlord) or pays the landlord directly.

Security Deposit — The deposit amount, if any, subject to provincial restrictions: Ontario allows only a last month's rent deposit (no damage deposit); BC allows up to half a month's rent as a damage deposit plus a pet damage deposit if applicable; Alberta allows up to one month's rent; Quebec prohibits all security deposits. Specify the conditions for return of the deposit at the end of the sublease.

Condition of Premises — A description of the unit's condition at the start of the sublease, ideally supported by a move-in inspection checklist with photographs. This protects both the sublessor (from subtenant damage claims) and the subtenant (from being held responsible for pre-existing damage).

Furnishings and Contents — An inventory of any furniture, appliances, or personal property left in the unit by the sublessor, their condition, and the subtenant's obligation to maintain and return them in the same condition, subject to reasonable wear and tear.

Sublessor's Ongoing Liability — A clear statement that the sublessor remains liable to the landlord under the primary lease for all obligations, including rent payment, property damage, and compliance with building rules. The subtenant's indemnification of the sublessor for losses caused by the subtenant's breach provides a secondary layer of protection.

Governing Law — The province whose Residential Tenancies Act, Civil Code (Quebec), or commercial tenancy legislation governs the sublease, and the applicable tribunal or court for dispute resolution (LTB in Ontario, RTB in BC, TAL in Quebec).