Are online ESA letters valid in Wisconsin?

What the law says

HUD FHEO Notice 2020-01: "documentation from the internet is not, by itself, sufficient to reliably establish that an individual has a non-observable disability or disability-related need for an assistance animal." A reliable letter requires the practitioner to have "personal knowledge of the individual."

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

HUD's 2020 guidance — applied in Wisconsin — does not categorically prohibit telehealth ESA letters, but it makes clear that a letter is "reliable" only when the practitioner has personal knowledge of the individual. A questionnaire-only website with no real clinical interaction generally would not satisfy this standard. A telehealth letter from a licensed clinician who has actually evaluated the patient through a synchronous (video or phone) session can be reliable. Some states layer additional rules on top — see this page's state-specific sections. Whether a particular letter from a particular provider would be honored by a particular landlord in Wisconsin is fact-specific.