No-pet clauses are void in Ontario. You can refuse to rent to no one over it — but you can still act once a specific pet causes real damage or a real problem.
Short answer
No, not on paper. Ontario's RTA makes "no pets" lease clauses void, and a landlord can't refuse an applicant, or evict an existing tenant, for the mere presence of a pet. What the Act does allow is action based on what a specific pet actually does — damage, allergic reactions in other tenants, or genuine safety concerns — and condo corporations can still ban pets through their own by-laws.
Treadstone Law's breakdown of void Ontario lease clauses states it directly: "No-pet clauses are void under the RTA. A landlord cannot refuse to rent to someone because they have a pet." Writing "no pets" into a lease, or turning down an application because the prospective tenant mentioned a cat or dog, doesn't hold up — the clause simply has no legal effect, the same way the Board treats other prohibited terms.
The Tribunal's own guide to the Residential Tenancies Act frames the exception narrowly: "a landlord can give a tenant notice based on the presence, control or behaviour of a pet the tenant is keeping, such as where a pet causes damage to the rental property." So the trigger is never the animal existing in the unit — it's a documented consequence: chewed floors, an allergic neighbour, aggressive behaviour toward other residents, or a breed genuinely prohibited by municipal by-law. Keep the record on the conduct, not the pet.
The void-clause rule is about the RTA, not condominium governance. A condo corporation's declaration or rules can still prohibit or restrict pets in the building, and a landlord leasing a unit inside that building has to comply with those rules regardless of what the RTA says about lease clauses — so "no pets" can be enforceable at the building level even where it can't be enforced at the lease level. This is the same distinction that comes up in whether a lease clause can actually stop a tenant's activity: the RTA sets a floor, but it doesn't override every other layer of rules a unit might sit inside.
A "no pets" refusal never reaches a service or support animal in the first place — that's decided under the Human Rights Code, not the RTA's pet rules. The Ontario Human Rights Commission's policy on rental housing puts the landlord's duty plainly: they must "assess and accommodate individual needs short of undue hardship," and disability is one of the grounds protected throughout the tenant-selection and occupancy process. Treating a support animal as a negotiable "pet policy" question — rather than a human-rights accommodation — is one of the more common ways landlords expose themselves here, separate from anything the RTA itself says about pets.
A 30-minute call is enough to tell you whether AI pays for itself here.
