What to Do When You Find Out Your Tenant Has an Unauthorized Pet

You find out your tenant has a dog. Maybe you saw it through the window. Maybe a neighbor mentioned it. Maybe you walked in for a maintenance visit and there it was. Now you have to figure out what you can actually do about it, and the answer depends almost entirely on what your lease says, or does not say.

If the Lease Is Silent on Pets

This is the uncomfortable scenario. A lease that says nothing about pets does not prohibit them. Courts in most states interpret a silent lease as permitting pets by default. If you never addressed the subject in writing, you have limited grounds to demand the pet be removed. The tenant can reasonably argue they had no reason to believe a pet was not allowed.

That does not mean you are completely without options. You can serve written notice that pets require landlord approval going forward, and require the tenant to either remove the pet or execute a pet addendum with a documented pet fee or deposit. Whether a tenant is required to comply with a mid-tenancy policy change depends on your state. In most cases, you cannot unilaterally add a prohibition mid-lease that was not there when the tenant signed. But you can address it at renewal, and you can add an addendum now with the tenant's written agreement.

The better lesson is forward-looking. A silent lease is a gap that invites exactly this dispute. Three words fixes it permanently: "No pets permitted." Or alternatively, a specific pet policy that defines what is allowed, under what conditions, and at what cost. Either approach eliminates the ambiguity that makes this situation hard to resolve.

If the Lease Prohibits Pets

A clear no-pets clause gives you standing to act. The tenant is in violation of the lease and you have a documented basis to address it. Here is how to do that correctly.

Start with written notice. Serve the tenant a written notice of lease violation identifying the specific clause, the nature of the violation, and a deadline to cure. Most states require a cure period before a landlord can take further action for a lease violation other than nonpayment of rent. California gives tenants three days to cure a curable violation. Texas requires a reasonable time. Florida requires seven days for the first violation, and the second occurrence within 12 months can be treated as incurable. Know your state's cure period before you serve notice, because a notice that does not comply with the statutory requirements can be thrown out.

Document the violation. Before and after serving the notice, document the pet's presence with photos or written records. If the tenant later denies having a pet or claims they removed it, you need evidence of the timeline. If the pet caused damage, document that separately as a damage claim distinct from the lease violation itself.

Give the tenant a path to compliance. The notice should offer two options: remove the pet by the stated deadline or execute a pet addendum that retroactively approves the pet under defined terms. This second option is worth offering because it turns a violation into a resolved situation and may produce a pet deposit or fee you would not otherwise have. Some landlords prefer a clean no-pets enforcement. Others prefer to monetize the situation and move on. Either is legitimate as long as it is handled in writing.

If the tenant does not comply. A tenant who receives a proper written notice with a cure deadline and neither removes the pet nor agrees to an addendum is in continuing breach of the lease. Depending on your state, that gives you grounds to serve a termination notice and ultimately file for eviction if the violation continues. Evicting over a pet is uncommon in practice because most tenants comply once formal notice is served. But the legal path exists when they do not.

The Service Animal and ESA Exception

This is the part that catches landlords off guard. A no-pets clause does not apply to service animals or emotional support animals. Under the federal Fair Housing Act, tenants with disabilities have the right to request a reasonable accommodation for an assistance animal, and landlords are required to grant that request unless it would cause undue hardship or pose a direct threat to others. This applies even in buildings with strict no-pets policies. It applies even if the animal is a breed or size the landlord would otherwise prohibit.

The distinction between a pet and an assistance animal matters legally. A service animal is a dog trained to perform specific tasks for a person with a disability. An emotional support animal provides therapeutic benefit through companionship and does not require specific task training. Landlords can ask for documentation of the disability-related need for an ESA, typically a letter from a licensed healthcare provider, but cannot require specific forms, certifications, or registration. Denying a reasonable accommodation request for an assistance animal, or charging a pet fee for one, is a Fair Housing Act violation with real financial consequences.

If a tenant who is in violation of a no-pets clause claims their animal is an ESA after receiving your notice, you are required to pause the enforcement process and evaluate the accommodation request in good faith. If the documentation is legitimate, the accommodation must be granted. If it is not, consult a tenant rights attorney before proceeding with enforcement to make sure your response is defensible.

Charging for Pet Damage

Whether the lease prohibited pets or was silent on them, if a pet caused damage to the unit, you can pursue that damage through the security deposit and small claims court. Damage is damage regardless of what caused it. Carpet destroyed by a dog, floors scratched by claws, or doors marked up by an anxious cat are all legitimate deductions from the deposit with proper documentation.

Document the pet-caused damage the same way you would any other: dated photographs, a move-in condition checklist showing the baseline, and paid repair invoices. A vague deduction for "pet damage: $800" is less defensible than a specific entry: "replacement of living room carpet due to pet urine saturation, three rooms, $780, invoice attached." The more specific the documentation, the harder it is to successfully dispute.

In states that allow non-refundable pet fees, a pet addendum executed after discovery of the unauthorized pet can include a fee that covers anticipated cleaning or damage costs. This is a cleaner arrangement than trying to recover everything from a general security deposit at move-out, and it formalizes the situation going forward.

Use the Situation to Fix the Lease

An unauthorized pet discovered mid-tenancy is a signal that the lease has a gap. Whether it is a missing no-pets clause, a missing pet addendum process, or a missing damage documentation requirement, something in the lease failed to prevent this situation or make it easy to resolve.

At minimum, add a pet addendum to the current lease that addresses the animal now present in the unit, any associated fees or deposits, and the tenant's obligation to cover pet-caused damage. At renewal, make sure the new lease has a clear and specific pet policy that does not leave any room for the same dispute to repeat itself.

A state-specific residential lease agreement includes a pet policy section that addresses permitted and prohibited animals, fee structures, and damage liability in language that holds up. It costs significantly less than one month of trying to resolve a pet dispute that a three-word clause would have prevented. If you are already in the middle of this situation and need to formalize a pet arrangement in writing, a signed pet addendum referencing the original lease and outlining the new terms is the document that closes the gap.