Carry-on A small pet can travel with you in the passenger cabin if the pet is small enough to fit comfortably in a kennel that is placed under the seat. Animals are never allowed out of the kennel during flight. If you are traveling with your pet, your pet can travel as accompanied baggage. An unaccompanied pet will travel as part of the cargo system. Animals in the cargo system are transported in pressurized compartments as those in the checked-baggage system.
Fees vary based on weight and size of the kennel.
Rules and Guidelines Look here for tips, guidelines, and questions to consider when your pet travels. Kennels You and United must follow USDA regulations on the size of your pet's kennel. The kennel must be sturdy, properly ventilated, and large enough for your pet to stand, lie down, and turn around freely. Terms and conditions 2000 United Air Lines, Inc.