If the animal was a pet during the time the pet fee was charged, you are unlikely to get a refund. If you paid a deposit however you should be able to get that back.

My apartment manager is telling me that I cannot get my monthly pet rent back even though my ESA has been registered since 2022 because I just now informed them she’s an ESA. I moved in in December. Should I be entitled to a refund of my pet rent? I have documentation stating she has been a registered ESA since 2022.

A certificate does not prove that a tenant has an emotional support animal. As a landlord, you are entitled to see a signed letter from a licensed health care professional. You might find this article on HUD’s ESA rules helpful: https://esadoctors.com/hud-housing-rules-emotional-support-animals/

In situations where a tenant’s pet later becomes an ESA, any pet deposit that was paid should be refunded since the animal is now a protected assistance animal.

Landlords are allowed to charge residents for actual damages caused by an ESA. The landlord must be able to prove the damage was actually caused by the animal.

If that cleaning fee is charged to all residents it may be allowed. If it is only being charged to you because you are an ESA owner, it may be a different story. In any case, a tenant is responsible for actual damage their ESAs cause to the property.