How to Pick the Right Pet Carrier for Air Travel
By Petmate | Published: 2026-10-16
Category: Buying Guides
A practical buying guide to airline-approved pet carriers: measure your pet, check cabin vs cargo rules, and choose a carrier that fits under the seat.
Quick answer
Start with your airline's current pet policy, then measure your pet's length and height while standing. Choose a carrier that lets your pet stand, turn around, and lie down without touching the top. For cabin travel, a soft-sided carrier that fits under the seat is usually the right call. For cargo or long trips, a hard-sided carrier like the Petmate Giant Litter Box is not suitable; instead, look for a dedicated travel kennel that matches your airline's rules.
Measure your pet before you shop
Airline pet carrier rules start with size, and size starts with your pet. Stand your cat or small dog next to a wall and mark the floor at the tip of the nose and the base of the tail. Then measure from the floor to the top of the head or ears. Add about 2 inches to each measurement so your pet can stand, turn around, and lie down without pressing against the sides. If your pet is between sizes, size up for cargo travel and stay within the airline's under-seat limit for cabin travel. Weigh your pet too, because most airlines set a combined pet-and-carrier weight limit for in-cabin travel.
Cabin vs cargo: two different carriers
In-cabin pet carriers must fit under the seat in front of you, so they are usually soft-sided and flexible. Cargo carriers are hard-sided and built for the hold, where they need a secure door, ventilation on multiple sides, and space for your pet to stand. Many airlines do not allow pets in cargo on certain routes or in extreme temperatures, so confirm your route before buying. If your pet is anxious or brachycephalic, cabin travel is usually safer when the airline allows it. For cabin travel, measure the under-seat space on your specific aircraft, not just the airline's general size chart. For cargo, check that the carrier meets IATA-style requirements your airline lists.
Fit, ventilation, and security details that matter
A good travel carrier has a leak-proof bottom, secure zippers or latches, and ventilation on at least two sides. Soft carriers should have a firm base so your pet is not standing on sagging fabric. Hard carriers need a door that locks and does not pop open if the carrier shifts. Remove loose collars and tags before travel so they cannot catch on the carrier. Line the bottom with an absorbent pad and bring a spare in case of accidents. Practice short car rides with the carrier weeks before your flight so your pet associates it with calm, not just travel day.
Decision rules for airline pet carriers
- Rule 1: Airline policy first: Check your specific airline's current pet carrier size, weight, and route rules before you buy. Policies change and vary by aircraft. Write down the exact under-seat or cargo dimensions your airline allows.
- Rule 2: Measure your pet, not the carrier label: Use your pet's standing length and height plus 2 inches of clearance. A carrier labeled 'medium' may still be too small for a tall cat. If your pet cannot stand and turn around, the carrier is too small.
- Rule 3: Match carrier type to travel type: Choose a soft-sided, under-seat carrier for cabin travel and a hard-sided, ventilated carrier for cargo. Do not use a litter box or open pan as a travel carrier. Cabin and cargo carriers are not interchangeable.
- Rule 4: Prioritize security and ventilation: Look for locking zippers or latches, ventilation on at least two sides, and a leak-proof bottom. Test the door and zippers before travel day. A carrier that opens unexpectedly is a safety risk.
- Rule 5: Acclimate before you fly: Leave the carrier open at home with treats and a familiar blanket for a week or more. Short positive sessions beat last-minute stuffing. A calm pet travels better than a perfectly sized carrier alone.
Petmate products that support the routine
- Petmate Classic Litter Scoop: The Petmate Classic Litter Scoop has antimicrobial protection and is made from durable plastic with Microban technology. A clean litter box before and after travel reduces odor and stress, and a scoop that resists bacteria and mildew is easier to keep sanitary between trips.
- Petmate Litter Catcher Mat 1/2 Circle: The Petmate Litter Catcher Mat 1/2 Circle is made from a soft, rubberized material with a webbed design that traps litter scatter as your cat exits the pan. If your pet stays in a carrier or a temporary setup during travel, a mat keeps the surrounding area cleaner and reduces tracking.
Who this guidance is for
Best for
- Owners flying with a cat or small dog in the cabin who need an under-seat carrier
- Travelers who want a repeatable way to measure their pet and compare airline rules
- People preparing a pet for a first flight and wanting to reduce stress
Not for
- Owners shipping a pet as cargo without checking the airline's specific cargo carrier requirements
- Pets that cannot stand and turn around in any carrier that fits the airline's under-seat size
- Travelers looking for a litter box or open pan to double as a travel carrier
