Does it need to be on letterhead?

No statute requires it, and a provider assessing reliability will find a document with checkable licence details more persuasive than one with a nice header and no number.

Does it need to name the animal?

Not by statute, and naming the animal makes the request concrete and is usually helpful.

How recent does it need to be?

No statutory expiry exists. Twelve months is the professional convention and a provider will discount something much older.

What a valid emotional support animal letter contains

How it worksLast reviewed Sep 15, 2026

Most rejected letters are rejected for something on this list, and almost all of it is fixable before you submit.

What has to be there

The clinician's name and professional credentials.
Their licence type, licence number, the state that issued it, and its expiration date. This is the part a housing provider can actually check, and the part most often missing.
A statement that you have a disability within the meaning of the Fair Housing Act. Not which one.
A statement that the animal alleviates one or more symptoms or effects of it.
The date of issue, and the clinician's signature.

What should not be there

Your diagnosis. A housing provider is not entitled to it, and including it hands over information you cannot get back.
Your treatment history, medication, or clinical notes.
Any claim that the animal is a service animal, or has public access rights. It does not, and that sentence turns a good letter into a liability.
A registration or certificate number, which signals the letter came from a mill.

What some states add

California requires the document to state the licence type, number, jurisdiction and effective date, and requires a thirty day client-provider relationship behind it. Montana requires licence type, number and effective date. Arkansas, Iowa and Louisiana each impose their own conditions. A letter that satisfies the general standard can still fail a state one.

The thing a letter cannot do on its own

Prove itself. A housing provider handed a PDF has no way to know it is genuine, which is why so much of this market is worthless paper. A letter issued here carries a six digit ESA ID and a public verification page, so a provider can confirm it is real and current without being shown anything about your health.

Common questions

Does it need to be on letterhead?: No statute requires it, and a provider assessing reliability will find a document with checkable licence details more persuasive than one with a nice header and no number.
Does it need to name the animal?: Not by statute, and naming the animal makes the request concrete and is usually helpful.
How recent does it need to be?: No statutory expiry exists. Twelve months is the professional convention and a provider will discount something much older.