Understanding Allegiant Air’s Pet Policy for 2025

Flying with a pet can feel like navigating a maze of rules, but Allegiant Air’s approach is intentionally narrow—and strictly enforced. The airline only accepts small cats and dogs in the passenger cabin, and it never transports animals as checked baggage or cargo. That means every decision from booking to boarding must align with a compact set of requirements. This guide unpacks every detail you need for 2025 travel: who can fly, what the carrier must look like, how much you’ll pay, where documentation is required, and what to expect at the airport and in the air. If you prepare correctly, a low‑cost Allegiant flight can be a smooth experience for both you and your pet.

Eligible Pets and Route Restrictions

Allegiant only welcomes domestic cats and dogs in the cabin. Birds, rabbits, reptiles, rodents, and any other species are not permitted under any circumstances—even if the animal fits inside an approved carrier. Your pet must never leave the cabin because Allegiant completely eliminates the option of checked or cargo hold travel.

Route limitations are absolute: pets are allowed solely on domestic flights within the contiguous United States. If your itinerary includes an international destination (even popular Allegiant routes to Mexico or the Caribbean), your pet cannot accompany you. Connecting flights are treated as separate segments, and every single leg must be a domestic route that permits pets. Before you book, verify that your entire journey—layovers included—stays within the eligible network.

There is no explicit weight cap, but the animal must fit comfortably inside a carrier that slides entirely under the seat. The airline caps the total number of pets on any flight at six, and each passenger may bring only one pet. If you need to travel with more than one animal, you’ll require a second ticketed traveler. Young animals must be at least eight weeks old and fully weaned; while not printed as a written rule, Allegiant enforces this at check‑in based on widely accepted aviation and veterinary standards.

In‑Cabin Pet Travel: Carrier Dimensions, Fees, and Personal Item Rules

The carrier is the single most important piece of equipment. Allegiant’s maximum allowed dimensions are 9 inches high x 16 inches wide x 19 inches deep. You can use a soft‑sided or hard‑sided carrier as long as it is leak‑proof, well‑ventilated, and securely latched. The carrier must fit completely under the seat in front of you without being crushed or protruding into the aisle. Soft‑sided carriers are often easier to shape into the limited space, but they must still meet the 9‑inch height when fully packed and zipped.

The pet fee is $50 per pet, per flight segment. A round‑trip journey with a layover in each direction could add $200 or more in pet fees. The charge is collected when you add the pet to your booking—either during online purchase or later by phone—and it is non‑refundable unless you cancel the entire reservation within the 24‑hour flexible cancellation window.

One rule that often catches travelers off guard: the pet carrier counts as your free personal item. Allegiant’s standard allowance includes one personal item that fits under the seat, but when you bring a pet carrier, that item is your personal item. You cannot bring an extra purse, laptop bag, or backpack for free. You can still purchase a carry‑on bag (fees vary from about $15 to $35 depending on when you pay), but that bag must go into the overhead bin. Any other personal belongings you need during the flight must fit inside the paid carry‑on or your pockets. Pack smart, or you’ll face extra charges at the gate.

Step‑by‑Step Booking Guide for Pet Travel

Reserving your pet’s space is an extra step that cannot be skipped. Because Allegiant limits each flight to six pets, early booking is critical, especially near holidays or popular travel dates.

1. Adding a pet during online booking

When you book on Allegiant’s website, the “Travelers” page presents an option to “Add a pet to your trip.” The system automatically applies the $50 fee per segment and displays the total. Once you pay, the pet is confirmed. You’ll receive an itinerary that lists the pet carriage.

2. Adding a pet to an existing reservation

If you’ve already purchased your ticket, you must call Allegiant customer service. Have your confirmation code ready. The agent will confirm your flight details, verify that the route still permits pets, and collect the fee. It’s wise to have your carrier’s dimensions on hand because the agent may ask for them. After payment, you’ll receive an updated itinerary showing the pet.

3. What to do at the airport

Even if you’ve added the pet and paid, you must visit the Allegiant ticket counter on travel day. Online check‑in may be available for you, but the pet requires a face‑to‑face inspection. A gate agent will measure the carrier, confirm the animal appears healthy, and place a “pet in cabin” tag on the carrier before you proceed to security.

For itineraries with connections, remember that the fee applies to each segment. A flight from Nashville to Phoenix with a stop in Denver costs $50 for the first leg and $50 for the second, totaling $100 one‑way. Always verify the total when you book.

Checked Pets and Cargo Are Not an Option

One of the most consequential parts of Allegiant’s policy is what it does not allow: there is no checked baggage or cargo option for live animals. If your dog or cat is too large to fit comfortably in an under‑seat carrier, you simply cannot fly with that pet on Allegiant. Owners of medium and large animals have a few alternatives:

  • Road trips: For shorter distances, driving eliminates airline restrictions and often reduces stress for the animal.
  • Third‑party pet transport services: Companies that specialize in pet relocation can arrange ground or air transport using cargo‑friendly airlines. Look for providers with proper USDA licensing and clear safety records.
  • Another airline: Several U.S. carriers still transport larger pets in the cargo hold under controlled conditions, though breed restrictions and temperature embargoes apply. Compare airline policies before booking a human ticket.

Because Allegiant’s model is entirely cabin‑based, it is best suited for small‑to‑toy breeds and cats that comfortably fit the carrier dimensions. If your pet is a Labrador or a Maine Coon cat, plan to make alternate travel arrangements.

Breed and Behavioral Restrictions

Allegiant does not maintain a blacklist of banned dog breeds. Unlike some airlines that prohibit snub‑nosed (brachycephalic) dogs such as Bulldogs, Pugs, or Boston Terriers, Allegiant allows them to travel. However, this does not mean there are no behavioral checks.

Crew members and gate agents have the authority to deny boarding to any pet that shows aggression, persistent barking, growling, or signs of extreme distress. The decision is final, and refund of the pet fee is not guaranteed if boarding is refused for conduct reasons.

If you own a brachycephalic breed, take extra precautions even though Allegiant permits them. These animals can struggle with breathing under stress, cabin pressure, or heat. Visit your veterinarian for a pre‑flight wellness check, consider a lightweight carrier with extra ventilation, and avoid any sedation unless specifically prescribed and supervised by the vet.

Your pet must stay inside the carrier at all times from the moment you clear security until you exit the aircraft at your destination. There are no provisions for walking the animal inside the terminal or using a travel litter box. Be prepared with an absorbent pad inside the carrier and a small clean‑up kit for accidents.

Service Animals vs. Emotional Support Animals

Federal rules draw a sharp line between trained service dogs and emotional support animals. Allegiant follows the U.S. Department of Transportation (DOT) regulations exactly.

Service dogs—defined as dogs individually trained to perform tasks for a person with a disability—are welcome in the cabin free of charge. They are not required to stay in a carrier, but they must be leashed, harnessed, or otherwise tethered, and they must fit at the passenger’s feet without obstructing the aisle. Travelers must submit the DOT Service Animal Air Transportation Form (and, for flights longer than eight hours, a relief attestation) at least 48 hours before departure. You can upload these documents on Allegiant’s website or present them at the ticket counter. For additional DOT guidance, see the official service animal page.

Emotional support animals (ESAs) are no longer recognized as service animals. Since 2021, ESAs travel under the standard pet policy. That means the animal must fit inside an approved carrier, you must pay the $50 fee per segment, and all in‑cabin rules apply. If your ESA is a large dog, it cannot fly on Allegiant. There is no exception for therapeutic value.

Health Documentation and State Regulations

Allegiant does not require a health certificate for in‑cabin pets. That does not release you from responsibility, however. Many U.S. states enforce their own animal health import rules, and you could be asked to show a Certificate of Veterinary Inspection (CVI) and proof of rabies vaccination at your destination. States like Florida, Massachusetts, and especially Hawaii (though Allegiant rarely serves the islands) have strict requirements. Check the USDA APHIS Pet Travel website for current rules for each state you will enter or transit.

Even when no certificate is mandatory, a quick veterinary visit before travel is wise. Make sure vaccinations are up to date, and ask your vet about motion‑sickness management or calming aids that are safe for flight. Ensure your pet wears a collar with an ID tag displaying your mobile number, and that its microchip registration is current. Kittens and puppies must be at least eight weeks old and fully weaned; any younger animal risks being denied boarding.

Preparing Your Pet for Air Travel: A Detailed Checklist

Start your preparation at least two weeks before departure. A calm, familiar‑feeling experience dramatically improves the flight. Here is a thorough checklist to follow:

  • Carrier acclimation: Leave the open carrier at home with a soft blanket and treats. Encourage your pet to explore it on its own. Gradually close the door for short periods, extending the time until the carrier feels like a safe den. For cats, a familiar‑scented cloth can reduce anxiety.
  • Pre‑flight veterinary check‑up: Have your vet clear your pet for travel. Discuss anxiety, motion sickness, and whether any prescription anti‑nausea or calming medication is appropriate. Never use human over‑the‑counter drugs without explicit veterinary advice.
  • Feeding and hydration: On flight day, offer a light meal three to four hours before departure. Water can be offered right up until you leave for the airport. Attach a no‑spill water bowl or a frozen bottle to the carrier door for in‑flight hydration, but remove it during active movement to avoid spills.
  • Exercise before leaving: A long walk, a vigorous play session, or a feather‑wand chase can help your pet settle down and sleep during the flight.
  • Pack a “pet go‑bag”: Include an extra absorbent pad, a ziplock bag with a few high‑value treats, a collapsible water dish, waste bags, a small towel, and a sealed packet of cleaning wipes. A familiar toy or chew item can provide comfort.
  • Identification and papers: Carry a copy of vaccination records and any required health certificates in a waterproof sleeve. Attach a temporary tag with your destination address and phone number in addition to the permanent ID.
  • Practice the carrier with movement: Walk around the house carrying the carrier, simulate a short car ride, and let your pet get used to the motion. Reward calm behavior.

Arrive at the airport at least two hours before departure to comfortably complete the extra steps required for pet travel.

Ticket counter check‑in

You must visit the Allegiant ticket counter. The agent will inspect the carrier dimensions, make sure the pet is visible and looks healthy, and attach a tag. This step cannot be bypassed with online check‑in alone.

TSA screening

At the security checkpoint, remove your pet from the carrier and place the empty carrier on the X‑ray belt. Hold your pet or lead it through the metal detector on a leash and harness. If your pet is anxious, you can request a private screening room where a TSA officer will inspect the carrier manually. More tips are available on the TSA traveling with pets page.

Boarding and in‑flight rules

Once at the gate, keep your pet inside the carrier at all times. During boarding, slide the carrier under the seat in front of you as soon as you reach your row. The carrier must remain stowed for taxi, takeoff, landing, and whenever the seatbelt sign is illuminated. You cannot place it on an empty seat or in the overhead bin.

During the flight, speak softly to your pet but do not open the carrier. The white noise of the cabin often helps animals rest. If your pet becomes vocal or restless, gently reassure them without removing them from the carrier. You cannot leave the carrier unattended if you use the lavatory, so coordinate with a travel companion or wait until the seatbelt sign is off and you can move swiftly.

What Happens If Your Flight Is Delayed or Canceled?

Flight disruptions add stress, and when you are traveling with a pet, they can become complicated. Allegiant will rebook you and your pet on the next available flight as long as the trip remains on domestic routes and the pet limit has not already been reached. If the new flight is full on the pet count, you may have to wait for a later departure—or, in rare cases, the pet may not be able to travel on that day.

Keep in mind that the pet fee is generally non‑refundable, but if Allegiant cancels your flight and you choose not to rebook, the total value of your unused ticket—including pet fees—should be returned to your original form of payment. If you voluntarily move to another flight and the pet segment fee has to be paid again, contact customer service to discuss any potential adjustments.

During long delays, you cannot take your pet out of the carrier inside the terminal unless you are in a designated pet relief area, which most airports provide beyond security. Plan for this by carrying a portable water bowl and a few extra absorbent pads. If you have a layover, short walks to a relief area between flights can make a big difference.

Frequently Asked Questions

Can I bring two pets in one carrier?

No. Allegiant’s policy allows one pet per passenger and one pet per carrier. Even if two kittens could physically fit, the carrier must hold only a single animal. If you need to transport two pets, you’ll need a second ticketed traveler, each with a separate carrier.

Does my pet carrier count as a carry‑on or a personal item?

The pet carrier replaces your free personal item. You may still buy a carry‑on bag to put in the overhead bin, but you cannot also bring a purse or laptop bag for free. Consolidate personal items into the paid carry‑on or your pockets.

What if my pet becomes disruptive during the flight?

Allegiant reserves the right to refuse transport to any animal that is aggressive, continuously barking, or clearly distressed. While an occasional soft whimper is tolerated, sustained noise may lead to denied boarding or deplaning. Pre‑flight training and comfort measures greatly reduce this risk.

Can I let my pet out of the carrier to use a pee pad?

No. Pets must remain zipped inside the carrier for the entire flight. Use a high‑absorbency pad inside the carrier to manage accidents. There are no onboard pet relief areas.

Are emotional support animals allowed?

Emotional support animals travel under the standard pet policy. They must fit in an approved carrier, the $50 per‑segment fee applies, and all in‑cabin rules are the same as for any pet. Only trained service dogs meeting DOT criteria can fly for free and outside a carrier.

Key Takeaways and Final Recommendations

Allegiant Air’s pet policy works well for travelers with small cats and dogs who are comfortable inside a compact carrier on domestic flights. The airline’s cabin‑only approach keeps the process straightforward, but it also leaves zero flexibility if your pet doesn’t meet the size or species requirements.

To keep your trip smooth, remember these essentials:

  • Species and size: Only domestic cats and dogs that fit a 9″ H x 16″ W x 19″ D carrier may fly. No cargo option exists.
  • Routes: Pets are allowed solely on flights within the contiguous United States. International and overseas segments are off‑limits.
  • Fees and limits: The cost is $50 per segment, and only six pets total are accepted per aircraft. Reserve early.
  • Personal item: The carrier counts as your personal item; pack accordingly.
  • Service animals: Trained service dogs travel free with the correct DOT form, submitted 48+ hours in advance. ESAs travel as pets.
  • Health rules: Even without an airline‑mandated certificate, comply with state import regulations—check the USDA APHIS site for details.

For the most current policy, always consult Allegiant’s official traveling with pets page. Pair that information with the DOT service animal guidelines and practical screening advice from the TSA to eliminate surprises. With a compliant carrier, early booking, and a well‑prepared pet, you can enjoy a budget‑friendly Allegiant journey together.