Service dog vs ESA vs PSD: what actually flies

Three labels get mixed up all the time: service dog, PSD, and ESA. At the airport they lead to very different trips, so it's worth getting them straight before you book.

Service dog

Under the U.S. Department of Transportation rule, a service animal is a dog, of any breed or type, that is individually trained to do work or perform tasks for a person with a disability. That includes physical, sensory, psychiatric, intellectual, and other mental disabilities.

A service dog flies in the cabin with you, on your lap or in your foot space, at no charge. The airline can ask you for the official DOT Service Animal Air Transportation Form.

PSD (psychiatric service dog)

A PSD is a service dog. The trained task supports a psychiatric disability, but the rules are the same: same definition, same DOT form, same cabin rights. There is no separate PSD paperwork for flying, and you don't need a letter or a certificate.

ESA (emotional support animal)

The DOT rule says emotional support animals, comfort animals, and companion animals are not service animals. Airlines don't have to accept them as service animals, so on U.S. airlines an ESA generally flies under the airline's pet policy: a carrier that fits under the seat, plus the pet fee.

What about cats, or dogs in training?

The rule covers dogs only, and service animals in training are not covered. A cat, or a dog still in training, can usually still fly as a pet. PetPassGo builds that pet plan for you.

What PetPassGo will and won't do

We don't sell, sign, or attest a service-animal form, and we never ask you to buy a certificate or a letter. Your Travel Pass uses the official DOT forms after you Plan my trip and pay. It links to the airline's own page and tells you what to send and when.

Also read: Do you need a PSD letter to fly? and the DOT service animal form, explained.

Source: 14 CFR Part 382, Subpart E (definition in § 382.3, lap or foot space in § 382.77). Checked October 18, 2026.