"No pets" policies are generally legal
Outside of fair housing protections for assistance animals, there's no general federal or state right to keep a pet in a rental. A landlord can lease a "no pets" building, and can change that policy going forward for new tenants, the same way they set any other lease term. If your current lease allows pets, a landlord generally can't reverse that for you mid-lease, but they can decide not to renew a pet-friendly policy, or not to renew your lease at all, depending on your state's rules on non-renewal. A building can also allow pets in general while still excluding specific animals, so "pet-friendly" on a listing doesn't guarantee your particular pet will be approved.
Breed and weight restrictions are common — and generally legal too
Many landlords and insurers maintain lists of dog breeds — commonly including breeds sometimes perceived as higher-risk — that are excluded from a building, along with weight limits meant to capture large dogs regardless of breed. These restrictions are a standard part of many leases and are generally enforceable as ordinary lease terms, the same as a no-pets policy. A landlord doesn't need to justify a specific breed list to you, and there's no federal law that prohibits breed-based restrictions on ordinary pets.
The exception: assistance animals
A no-pets policy or a breed restriction cannot lawfully be used to deny a legitimate service animal or emotional support animal connected to a tenant's disability. The Fair Housing Act requires a landlord to consider waiving those very policies as a reasonable accommodation (42 U.S.C. § 3604(f)(3)(B); 24 CFR § 100.204(a)) — the accommodation exists specifically to override a "no pets" or breed-based rule, not to work around it. That said, a landlord can still raise a direct-threat objection to a specific animal's documented behavior, rather than to its breed in the abstract; a blanket breed exclusion applied automatically to an assistance animal, with no individualized look at that particular animal, is the kind of policy most likely to run into a fair housing problem.
Say a tenant's documented psychiatric service dog happens to be a breed on the building's excluded list. A landlord generally can't point to the breed list alone to deny the accommodation — they'd need to show that this specific dog poses a direct threat that can't be addressed another way, not just that its breed is on a general exclusion list applied to ordinary pets.
Insurance is usually what's driving a breed ban
Breed and weight restrictions in a lease often trace back to the landlord's liability insurance policy, which may exclude coverage for certain breeds or charge more to include them. That's a business decision the landlord is generally free to make for ordinary pets, but it also means a breed ban you're pushing back on may not be within the property manager's own discretion to waive, since insurance coverage sits above the lease — even a sympathetic property manager may not be able to override what their insurer will and won't cover.
Local breed-specific rules
Separately from anything in your lease, some cities and counties have their own breed-specific ordinances that restrict or require special handling for certain dogs regardless of what your landlord's policy says. Whether your city has one, and exactly what it covers, is a local-law question — check your city or county's own municipal code rather than assume a rule you've heard about elsewhere applies where you live.
What to check before you sign or get a pet
Before signing a lease or bringing home a pet, read the pet policy section closely: which breeds or weights are excluded, whether there's a limit on the number of pets, and whether the restriction applies to a pet you already have versus one you get later. If you already have a dog of a restricted breed, ask directly rather than assume it will be fine — misrepresenting a pet on a lease application is often treated as a lease violation on its own, separate from the pet issue itself. Honestkey™ can review your lease's pet policy and flag breed, weight, or number-of-pets restrictions before they become a problem — and note where an assistance-animal request should be treated differently from an ordinary pet application.