Taking your pup on a flight is more than just clicking "add pet" at checkout. Since airlines don't sell traditional "seats" to dogs (unless they are service animals or you use specific boutique carriers), your "ticket" is usually a flat fee added to your own reservation.
Proof of rabies vaccination is the standard minimum for domestic travel. buying a plane ticket for your dog
A unique option for medium-to-large dogs; allows you to buy a full-priced second seat for your dog to travel in the cabin with you. Traveling with pets - United Airlines Taking your pup on a flight is more
Look for a "Travel with a pet" toggle or a traveler dropdown menu. buying a plane ticket for your dog