? Are you looking for a compact, airline-approved pet carrier that fits under the seat on Frontier or Allegiant and keeps your extra-small dog or small cat comfortable during short flights?
Product overview
Common Mistake: A lot of people assume that 17x13x8 Frontier Allegiant Expandable Pet Carrier review is simple, but overlooking small details often leads to frustration. Avoid skipping the fundamentals!
You’ll find that the 17x13x8 Frontier Allegiant Airlines Approved top Expandable pet Carrier for Extra-Small Dog/Small cat, Weight up to 5 lbs, Length Shorter Than 16” is built with a clear purpose: safe, compact in-cabin travel for very small pets. The carrier focuses on meeting specific airline restrictions and giving your pet a little extra room when you need it.
What this carrier is meant for
This carrier is tailored to extra-small dogs and small cats that are shorter than 16 inches and weigh up to 5 lbs. You should measure your pet’s length first, since length is the critical factor for fitting under the seat — weight is secondary.
Who should not buy it
If your pet is taller than 16 inches or heavier than 5 lbs, this carrier is not suitable for long-term comfort or safety. You also should avoid this model if you frequently fly with airlines that require wider or taller carriers, such as Delta, United, American, or Alaska, because this carrier is not approved by those carriers.
Key specifications
You’ll want to know the specs at a glance to confirm whether this carrier fits your needs before purchasing. Below is a compact breakdown of the most important technical details and airline approvals.
| Feature | Detail |
|---|---|
| Product name | 17x13x8 Frontier Allegiant Airlines Approved top Expandable pet Carrier for Extra-Small Dog/Small cat, Weight up to 5 lbs, Length Shorter Than 16” |
| External dimensions | 17″ L x 13″ W x 8″ H (collapsed) |
| Expandable top | Adds 3″ height when fully expanded |
| Max pet length | 16 inches |
| Max pet weight | 5 lbs |
| Recommended pet | 1 extra-small dog or small cat |
| Airline approvals | Frontier, Allegiant (meets 18″x14″x8″ requirement); also accepted by Southwest/Spirit but not ideal |
| Not approved by | Delta, United, American, Alaska |
| Frames and support | 2 hard metal side frames; hard wood bottom padding |
| Safety features | Double zipper lock, anti-scratch mesh, internal tether |
| Storage | 2 zippered pockets |
| Carrying options | Adjustable shoulder strap |
| Washable parts | Soft padding in bottom (washable) |
| Warranty | 1-year warranty for product quality |
Design and materials
You’ll notice that the carrier uses both rigid and soft elements to balance stability and flexibility. Two hard metal frames on the sides and a hard wood padding at the bottom are included to prevent collapse and bottom sinking while still keeping the carrier lightweight and pliable.
Mesh and visibility
The expandable top features mesh on five sides to provide excellent air circulation and a 360-degree visual field for your pet. This is helpful because it allows your pet to see out without sacrificing ventilation or security.
Zippers, locks and finishes
You’ll appreciate the double zipper lock that helps prevent accidental openings and the anti-scratch mesh designed to withstand some clawing. The manufacturer also includes an internal tether to keep your pet secured and reduce the chance of escape.
Expandable top: how it works and when to use it
The expandable top gives you a practical option: collapsed for stowing under the seat during boarding, and expanded for giving your pet extra room when you’re not constrained by strict under-seat limits. That 3-inch increase in height can make a noticeable difference for your pet’s comfort during downtime.
Pros and cons of expandability
You’ll benefit from the added vertical space when the top is up, but you should be mindful that frames have limited elasticity and aren’t meant to be bent to much lower heights repeatedly. The expandability is best thought of as occasional extra room, not permanent tall-space living.
Best scenarios to expand the top
You should raise the top in the airport, during layovers, or on ground transport when under-seat restrictions don’t apply. Keeping the top expanded while boarding or when gate agents require strict under-seat compliance could cause issues, so collapse it when required.
Airline compatibility and tips for flying
Since you’ll likely buy this carrier because of airline travel, you should pay attention to the carrier’s airline approvals and the practical tips below. The dimensions are specifically chosen to comply with Frontier and Allegiant under-seat policies, so you’re primarily covered when flying with those carriers.
Specific airline notes
This carrier meets the 18″x14″x8″ requirement of Frontier and Allegiant and is noted as Southwest/Spirit approved, though those airlines often allow slightly taller options that may be more comfortable for your pet. It is not approved by Delta, United, American, or Alaska, so you’ll need a different carrier to travel with those carriers.
Pre-flight checklist for using this carrier on a flight
You should measure your pet and the carrier before you leave home, carry vaccination records if required by the airline, and ensure the top is collapsed if the airline enforces strict under-seat rules. Consider boarding early if you want to settle in with minimal stress for your pet and tuck the carrier under the seat following the crew’s instructions.
Fit and sizing: measuring your pet properly
You’ll save yourself frustration by measuring your pet correctly: length, height, and weight all matter, but the carrier emphasizes length first. Measure from the tip of the nose to the base of the tail — not including the tail — to get your pet’s length.
Why length matters more than weight here
This carrier is compact in height and width to meet airline restrictions, so a pet that is too long will be cramped even if it’s light. For your pet’s safety and comfort, ensure length is shorter than 16 inches and weight is 5 lbs or less.
How to check for a good fit
You should be able to fit your pet in the carrier with enough room to turn around, lie down, and stand without forced crouching. A good rule of thumb is about one to two inches of space at the head and tail when your pet is lying naturally.
Comfort inside the carrier
You’ll want the interior to be comfortable for short flights and car trips, and this carrier includes a soft, washable bottom padding to help. Adding a familiar blanket or a small comfort toy can reduce your pet’s anxiety and make the carrier feel like a safe den.
Ventilation and visibility comfort
The five-sided mesh on the expandable top enhances airflow and gives your pet visual access to surroundings, which helps reduce anxiety for many pets. You should keep an eye on your pet’s breathing and behavior; if panting or agitation occurs, consider taking short breaks off the plane when safe.
Padding and temperature considerations
The soft removable pad provides cushioning, but it may not be thick enough for very long journeys or for pets with joint issues. You should consider a thin memory foam pad if your airline trip is longer or your pet has special comfort needs, making sure the extra pad still allows the carrier to close properly.
Safety features explained
You’ll be responsible for keeping your pet secure, and this carrier includes several safety elements that help you do that. The hard metal side frames prevent collapse, the double zipper lock helps secure openings, and the internal tether can be clipped to your pet’s harness to limit movement.
How the built-in tether helps
The tether prevents your pet from bolting out when you open a door and gives you a bit of control during transitions. Always attach the tether to a harness rather than a collar to avoid neck injuries in the event of sudden movement.
Limitations of the safety features
You should be aware that while frames offer stability, they have limited elasticity and are not meant to be forced into unnatural shapes. The carrier provides solid protection for small pets, but it isn’t designed to substitute hard crates for heavy-duty transport or very large breeds.
Practical use beyond flying
You’ll likely find this carrier useful for short car trips, veterinarian visits, or brief stays away from home. It’s compact and portable, making it an ideal go-to for quick errands where bringing your pet along is necessary.
Using the carrier in a car
In a car, you should place the carrier on the floor behind the seat or securely on the seat with a seat belt looped through the strap or carrier handle where possible. Always make sure the carrier is stable so it won’t slide during turns or sudden stops.
Vet visits and short transports
You’ll appreciate the carrier’s quick-access zippers and pockets for storing paperwork, treats, or a small leash during vet visits. The compact size helps you carry your pet easily while you navigate clinic waiting rooms or public transit.
Storage and carrying convenience
You’ll find the adjustable shoulder strap helpful when you need hands-free mobility, and the two zippered pockets give you space for small essentials. The soft, collapsible nature means you can tuck the carrier away when not in use without taking up much room.
Pockets and storage uses
You should use the pockets for small items like waste bags, a small water dish, or proof of vaccinations to keep everything in one place. Avoid overfilling the pockets if you want the carrier to slide under seats easily and keep a balanced weight distribution.
Portability tips
You’ll find it easier to move around with the adjustable shoulder strap if you use both shoulders or switch sides periodically to reduce strain. Carrying the carrier with a hand under the bottom once in a while also gives your pet more stability and comfort.
Cleaning and maintenance
You’ll be glad that the bottom pad is washable, making it easier to keep odors and fur under control. Regular maintenance like brushing out hair, spot-cleaning the mesh, and wiping down the exterior helps prolong the carrier’s life.
Removing and washing the padding
You should remove the soft bottom pad and follow the manufacturer’s washing instructions — typically gentle cycle or hand wash and air dry. Make sure the pad is fully dry before putting it back in the carrier to avoid mildew.
Zipper and mesh care
You’ll want to keep the zippers clean and free of debris, and occasionally apply a zipper lubricant if they get sticky. Be gentle with the mesh when cleaning to avoid stretching or tearing, and check for holes periodically to repair before travel.
Training your pet to accept the carrier
You’ll get far smoother travel days if you acclimate your pet to the carrier in advance. Start by leaving the carrier open in your living space with familiar bedding and treats inside so your pet can approach at their own pace.
Step-by-step crate-training approach
You should begin by making the carrier a positive place: place treats, toys, and short feedings inside, and gradually encourage longer stays. Once your pet is comfortable, try short sessions closing the carrier for a minute or two and build up the duration until they tolerate the length of your intended travels.
Tips for reducing travel anxiety
You’ll find calming aids like pheromone sprays, a favorite toy, or a familiar-smelling blanket can help manage anxiety. Always avoid sedating your pet without consulting a veterinarian, as sedatives can affect breathing and balance during travel.
Pros and cons
You should weigh both the benefits and limitations so you can decide if this carrier matches your needs. Below are practical pros and cons to help with that decision.
Pros
You’ll like that this carrier is specifically sized for Frontier and Allegiant under-seat requirements and that it offers an expandable top with five-sided mesh. The built-in stability features, washable pad, and internal tether add useful safety and comfort.
Cons
You should be aware that the carrier is strictly for very small pets — pets longer than 16 inches or heavier than 5 lbs won’t fit comfortably. It’s not universally approved by all airlines, so you’ll need another solution for Delta, United, American, or Alaska flights.
Comparison with other airline carriers
You’ll notice that different carriers prioritize different features: some prioritize height, while others prioritize width or a more rigid structure. This particular model prioritizes low height and compactness to meet strict under-seat limits for certain airlines.
How it compares to 9″ height carriers
You should consider a 9″ height carrier if you fly frequently on Southwest or Spirit and want slightly more vertical space for your pet. However, those carriers might be too tall for Frontier/Allegiant policies; this carrier hits the sweet spot for their requirements.
How it compares to harder-sided carriers
You’ll find hard-sided carriers are often more protective in rough handling scenarios, but they can be heavier and less flexible for stowing under seats. This soft-sided expandable model offers a balance of protection, ventilation, and compactness, which is ideal for calm, small pets on short flights.
Warranty and customer support
You’ll appreciate that the product comes with a one-year warranty covering quality-related issues. The warranty includes zippers, buckles, hooks, and fabric, which gives you some peace of mind if anything fails prematurely.
What to do if something breaks
You should document the issue with photos and reach out to the seller or manufacturer with your purchase details and warranty claim. Quick communication and clear evidence usually help speed up replacements or repairs.
Limits of the warranty
You’ll need to be mindful that normal wear-and-tear, damage from misuse, or issues from airline handling may not be fully covered. Keep receipts and register the product if required to make warranty claims smoother.
Practical buying tips and checklist
You should check key items before hitting purchase, like exact measurements, airline policy updates, and your pet’s temperament for travel. Confirm the carrier’s acceptance with your airline and measure both your pet and the carrier to avoid surprises at the gate.
Pre-purchase checklist
You’ll want to confirm pet length is under 16 inches, weight under 5 lbs, and that your airline remains one that accepts this carrier. Also verify return policies, warranty registration, and what’s included (strap, pad, tether).
Accessories you might want
You should consider a small disposable or collapsible water dish, a thin extra pad for comfort, and a lightweight harness to clip to the internal tether. A calming pheromone spray or treat pouch for travel also improves the experience.
Frequently asked questions
You’ll likely have practical questions about specifics like airline approval, sizing, and what to expect in everyday use. Below are common questions and clear answers to help you decide.
Can I use this carrier on Southwest or Spirit?
You can use the carrier on Southwest or Spirit; both airlines typically accept carriers of this size. However, some passengers prefer a 9″ height carrier for those airlines, which gives slightly more vertical space.
Is this carrier approved by Delta, United, American, or Alaska?
No, this carrier is not approved by Delta, United, American, or Alaska. Those airlines often require a different dimension profile — wider in some cases — so you’ll need a different carrier for flights with those carriers.
How should I measure my pet to ensure it fits?
You should measure from the tip of the nose to the base of the tail (not including the tail) while the pet is standing or lying naturally. If that length is under 16 inches and the pet weighs 5 lbs or less, it should fit.
Final verdict
You’ll find the 17x13x8 Frontier Allegiant Airlines Approved top Expandable pet Carrier is a solid choice if your priority is meeting Frontier or Allegiant under-seat rules while giving your extra-small dog or small cat occasional extra headroom. If your pet meets the size criteria and you primarily fly on the approved airlines, this carrier combines stability, ventilation, and practical travel features in a compact package.
Who should buy it
You should buy this carrier if your pet is under 16 inches in length, weighs 5 lbs or less, and you often fly Frontier or Allegiant. It’s also a strong option for short car trips and vet visits where compactness and portability matter.
Who should look elsewhere
You should look for an alternative if your pet is larger, if you regularly fly on airlines that don’t accept this model, or if you need more rugged, heavy-duty transport for longer journeys. For those needs, a larger soft-sided carrier or a hard crate will be a better fit.
If you want, I can help you compare this carrier directly with specific models you’re considering or walk you through measuring your pet step-by-step so you can be confident in your choice.
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