Can a PMHNP or therapist write an ESA letter?

Yes. HUD's guidance lists physicians, psychiatrists, psychologists, physician assistants, nurse practitioners, and nurses among the professionals whose documentation can reliably support a housing request. State statutes can narrow that list or add conditions, and California's rules apply to every licensed health care practitioner, so the 30-day and licensure requirements bind a PMHNP exactly as they bind a psychiatrist.

How long is an ESA letter good for?

Federal law sets no expiration date. In practice, landlords commonly ask for documentation issued within the past year, so expect renewal requests roughly annually. Treat a renewal as a smaller fresh evaluation: confirm the condition, the benefit, and the animal are unchanged, document that, and bill it like the original letter.

Should You Write ESA Letters? A Policy You Can Defend

Yes, a psychiatrist can write an emotional support animal letter, and under HUD's 2020 guidance a note from the clinician actually treating the patient is the most reliable documentation a tenant can hand a landlord. Whether you should write one for a given patient is a separate question, and deciding it fresh with every request produces inconsistent letters, awkward sessions, and the occasional board-reportable shortcut. The workable answer is a practice policy: defined criteria, a published fee, an intake paragraph that sets expectations, and a decline script for requests the record cannot support. This guide gives you all four.

This is practice-operations guidance and none of it is legal or medical advice. Questions about a specific letter, patient, or state statute go to your attorney and your malpractice carrier.

What does an ESA letter legally do?

It asks a housing provider for a reasonable accommodation under the Fair Housing Act: your patient has a condition that substantially limits a major life activity, the animal alleviates a symptom or effect of that condition, and a no-pets policy therefore has to yield. The operative federal document is HUD's Assistance Animals Notice, FHEO-2020-01, issued January 28, 2020. Once the accommodation is granted, the animal is exempt from pet fees, pet deposits, and pet rent, though the tenant still pays for any damage it causes. The landlord may request reliable documentation of a disability-related need that is non-obvious; the landlord may never demand the diagnosis, severity details, medical records, or an examination.

The letter's power stops at the apartment door:

Where the patient wants the animal	Governing law	Does your letter matter?
Rental housing	Fair Housing Act, HUD 2020 guidance	Yes. Documentation from a treating clinician is what the landlord may request
Airplane cabin	Air Carrier Access Act, DOT final rule effective January 2021	No. Airlines may treat ESAs as pets and charge pet fees
Stores, restaurants, hotels	ADA	No. Public-access rights cover trained service dogs only, with no letter involved either way

Patients regularly conflate the categories, so expect to spend a minute of the conversation separating them. Under the ADA, a service animal is a dog individually trained to perform tasks directly related to a disability, and it needs no letter at all: a business may ask only whether the dog is required for a disability and what task it performs. An emotional support animal has no training requirement and can be any animal commonly kept in households. And when a patient asks about flying, the answer changed with the DOT final rule published in December 2020: airlines are no longer required to seat ESAs, so the letter that once boarded a dog now does nothing at the gate.

When is writing one clinically defensible?

Writing the letter is defensible when the chart already supports every sentence in it: an established treatment relationship, a diagnosed condition that substantially limits at least one major life activity, and an identified symptom or effect the animal alleviates. That standard comes from HUD's own documentation guidance, which asks clinicians to write from personal knowledge, general to the condition and specific to the individual. A 2023 review in Psychiatric Services (Binder and colleagues) lands in the same place, recommending a real evaluation behind every letter: the diagnosis, the functional impairment, and the specific way this animal mitigates it, documented the way you would document any clinical decision.

Honesty runs in both directions. The evidence base for ESAs specifically is thin, which the Psychiatric Services authors say plainly, and the letter is a formal disability attestation. At the same time, for the right patient, the depressed patient whose dog is the reason the morning starts, or the anxious patient visibly steadier since the cat arrived, the accommodation is real, cheap, and clinically coherent, and a blanket refusal serves nobody. Juan Rodriguez, MD, who reviewed this guide, draws the line this way: "Treat an ESA letter like a prescription. If the condition and the benefit are already visible in the chart, I write it and document it. If the letter would be the first place either one appears, that is my answer."

Which state laws now regulate ESA letters?

A growing list of states regulates who may write an ESA letter and after how much treatment, and California is the template. AB 468, in force since 2022 and verified against the current code in August 2026, requires a practitioner documenting the need for an emotional support dog to hold an active license and list its number, type, jurisdiction, and effective date in the letter itself; to be licensed for the jurisdiction where the documentation is provided; to complete a clinical evaluation; to have established the client-provider relationship at least 30 days before writing; and to notify the patient that misrepresenting a pet as a trained service dog is a misdemeanor. Violations are grounds for board discipline.

Two traps travel with this. The first is jurisdiction: the housing sits where the patient lives, and California expects the letter writer to be licensed for that jurisdiction, so a telehealth panel spread across states needs the same licensing discipline for letters as for seeing the patients themselves. Florida points the same direction, allowing out-of-state telemedicine providers to write one only after at least one in-person visit, per PRMS's summary of state law. The second trap is the waiting period: a patient who books an intake on Monday and wants a letter by Friday is asking you to violate a statute in a 30-day state. Requirements differ state to state, so confirm your own board's rules before you set policy.

What is your actual liability if you sign?

Smaller than clinicians fear, provided every sentence in the letter is true, and your carrier would rather you decline than stretch. PRMS, a professional liability program that insures psychiatrists, is blunt in its 2023 guidance: "The psychiatrist should be comfortable denying any inappropriate requests." Its checklist for the letters you do write is short: write only for a patient currently in treatment, disclaim any knowledge of the animal's behavior, never embellish to make the patient happy, and comply with your state's statute.

The exposure clinicians worry about most, a claim after the certified animal bites someone, is the reason for that disclaimer: your letter attests to the patient's clinical need for emotional support, never to the temperament, training, or safety of a particular animal, and it should say so. The exposure with a statutory hook is the cursory letter: California made AB 468 violations board-disciplinable, and a five-minute evaluation sold for a fee is exactly what the statute targets. A documented evaluation, a chart that supports the letter, and a copy of the letter in the record close off both.

Why do the online letter mills matter to your policy?

Because HUD has already discounted their product, and their customers end up back in your office. The 2020 notice addresses websites that sell ESA certificates after a short questionnaire and a fee, stating that in HUD's experience such internet documentation is "not, by itself" sufficient to reliably establish a disability or a disability-related need. The same passage names the reliable alternative: a note from a licensed professional with personal knowledge of the patient, including care delivered by legitimate telehealth. Landlords and their attorneys have read that paragraph. A patient who buys a mill letter and gets challenged will ask you for a real one, and statutes like AB 468 exist because legislatures got tired of the mills. Your letter, written from the chart after an evaluation, is the document the system is built to trust, which is an argument for having a policy instead of a reflexive no.

What goes in the letter itself?

One page, written from the chart, covering the elements HUD's documentation guidance recommends:

The patient's name, and a statement that you have a professional relationship with them involving their care, including since when.
The type of animal the accommodation is for.
That the patient has a condition that substantially limits one or more major life activities. The diagnosis itself is never required, and HUD bars landlords from demanding it.
That the animal does work, provides assistance, or provides emotional support that alleviates at least one identified symptom or effect of the condition, described in general terms.
Your signature, the date, your contact information, and your license details, which are mandatory letter contents in California.

If the animal is anything beyond a dog, cat, or other small domesticated species, HUD places a "substantial burden" on the request, and the letter should add the date of the last consultation, the unique circumstances requiring that particular animal, and whether you specifically recommended it. Leave out prognosis promises, treatment details, and anything describing the animal's temperament or training, which you are explicitly disclaiming anyway.

What should your practice policy say?

Decide four questions once, in writing: who qualifies, who evaluates, what it costs, and how you decline.

The request	Default policy
Established patient, condition and benefit already documented	Write it at a scheduled visit, document the evaluation, bill at your paperwork rate
Established patient, request outruns the chart	Evaluate first, then write only what the evaluation supports
New caller whose stated goal is a letter this week	Decline at screening; in a 30-day state the timeline alone can violate the statute
Patient located where you hold no license	Decline and explain the jurisdiction rule

On fees: an ESA letter is paperwork, so it runs through the same published-rate machinery as every other form and letter, and a request that requires a fresh evaluation is a visit, billed as one. Publishing the fee and the criteria in advance is what keeps the eventual conversation clean, which is why the policy belongs in your intake packet rather than in an email sent after the request lands. Your phone screen should also catch the caller whose only goal is the letter, the same filter described in screening new patients.

Intake policy paragraph, for the office-policies section of your intake packet:

Letters and forms policy: I complete letters and forms, including
emotional support animal (ESA) letters, only for established
patients, and only when my clinical evaluation and your record
support what the document asks me to attest. ESA letters also
depend on state law, which may require a minimum length of
treatment before a letter can be written. Requests are handled at
scheduled appointments and billed at the paperwork rate on my fee
schedule. Starting treatment does not guarantee any particular
letter.

Decline script, for the session where you say no. Say it, then chart that you said it:

I want to help with the housing situation, and I need to be
straight with you about what this letter is. It is my formal,
signed statement that you have a condition that substantially
limits your daily life and that this animal relieves part of it.
Based on what is in your record today, I cannot make that
statement. Declining the letter changes nothing about your
treatment here. If your symptoms and our work together change
that picture, I am glad to revisit it.

Most patients accept a clear decline delivered without judgment, especially when the intake paperwork predicted it months earlier. The rare patient who makes the letter a condition of the relationship has turned a paperwork question into a boundary question, and if it ends the treatment, the exit follows the same careful sequence as any other discharge.