Can a landlord say no to pets in Canada?
In most provinces, yes — a landlord can refuse pets or enforce a 'no-pet' clause if it's written into the lease. Ontario is the key exception: there a no-pet clause is void once you've signed, so you generally can't be evicted just for having a pet unless it causes damage, a serious disturbance, or allergic reactions, or is a dangerous breed.
Ontario stands alone. Under the Residential Tenancies Act a no-pet clause has no effect once the lease is signed, though a landlord can still decline a pet-owning applicant before signing.
In BC, Alberta, Quebec, and the rest of Canada, a no-pet clause in the lease is generally enforceable. One rule is nationwide: certified service animals are protected under human-rights law and can't be refused or charged a fee.