What is an emotional support animal (ESA) letter and how does it work in Missouri?

What the law says

HUD's 2020 guidance (FHEO Notice 2020-01) describes ESA documentation: "A reliable third-party who is in a position to know about the individual's disability may also provide verification of a disability."

Source: HUD FHEO Notice 2020-01: Assessing a Person's Request to Have an Animal as a Reasonable Accommodation Under the Fair Housing Act ↗

In plain language

In Missouri, an ESA letter is a written statement from a licensed healthcare professional supporting a tenant's request for a reasonable accommodation under the federal Fair Housing Act. The letter typically describes the existence of a disability and how the animal alleviates symptoms — without disclosing the underlying diagnosis. As of 2026, federal HUD enforcement of ESA housing accommodations narrowed to trained animals, so whether an untrained ESA is protected in Missouri now depends largely on state law (see the protection summary at the top of this page). The letter remains supporting documentation that establishes a disability and aids a reasonable-accommodation request — it does not, by itself, compel a landlord, and no provider can guarantee a landlord will accept it. Whether a particular landlord honors a particular letter is fact-specific; tenants who believe a request was wrongfully denied generally consult a HUD-certified housing counselor or a fair-housing attorney licensed in Missouri.