Delta Airlines Pet Carrier Dimensions: The 18 x 11 x 11 Inch Rule Explained (2026)

Delta Air Lines recommends a soft-sided in-cabin pet carrier with maximum dimensions of 18 x 11 x 11 inches (about 46 x 28 x 28 cm), because that size fits under the seat on most Delta aircraft. Delta airlines pet carrier dimensions are the size limits a kennel must meet to ride in the cabin under the seat in front of you. As of September 2026, Delta says the true maximum depends on your specific aircraft, so confirm with Delta Reservations before you fly.

This guide sets out Delta's current in-cabin kennel rules, seat and cabin limits, fees and age minimums, drawn from Delta's own consumer and travel-agent policy pages. It also points out where those pages contradict each other. It was last updated on September 30, 2026, by the editorial team at Animal Passport.

Delta pet carrier dimensions at a glance

The table below summarises the in-cabin kennel rules Delta Air Lines published on its Pet Travel Overview page, as checked in September 2026.

Why 18 x 11 x 11 inches is a recommendation, not a hard limit

Delta does not publish one universal maximum carrier size. On its Pet Travel Overview page (checked September 2026), Delta Air Lines states that "the maximum in-cabin kennel dimensions are determined by the aircraft dimensions of your flight, as the under-seat space varies by aircraft," and recommends 18 x 11 x 11 inches "since this fits most aircraft types."

In practice, that means:

• A carrier within 18 x 11 x 11 inches is the safest choice across Delta's mainline fleet.
• A slightly larger carrier may fit on some aircraft, but Delta does not guarantee it.
• Regional jets operated as Delta Connection flights can have different under-seat space and policies. Delta's travel-agent policy page says Delta Connection flights "have different capabilities and policies concerning pets."
• If your trip includes an aircraft swap, the smallest under-seat space on your itinerary is the one that counts.

The height limit is usually the tightest of the three. A soft-sided carrier that compresses slightly under a seat frame is more forgiving than a rigid box, which is one reason Delta recommends soft-sided kennels.

Soft-sided or hard-sided? Where Delta's own pages disagree

Delta's published sources do not say the same thing about kennel construction, so check with the airline before relying on any single page:

• Delta Pet Travel Overview (consumer site, 2026): recommends a soft-sided kennel that is leak-proof and has ventilation openings on 3 sides for domestic travel and 4 sides for international travel.
• Delta Professional travel-agent Pet Policies page: says "either soft- or hard-sided kennels must be leak-proof and ventilated on at least two sides."
• Delta Pet Travel Requirements & Restrictions page (older consumer page, still online): also says soft- or hard-sided kennels are acceptable if they are leak-proof and ventilated on at least 2 sides.

The safest reading is to use a soft-sided, leak-proof carrier with mesh ventilation on at least 3 sides, or 4 sides for international flights. That meets every version of the rule. A gate agent at the Special Service Counter makes the final call, and Delta says the agent will check that your pet and kennel meet requirements at check-in.

How to measure your pet carrier for a Delta flight

Delta asks you to have your kennel's length, width and height ready when you call Reservations to add your pet. Use these steps:

1. Measure the outside of the carrier, including pockets, wheels, frames and handles that stick out, not just the fabric body.
2. Record length x width x height in inches (Delta publishes its guidance in inches).
3. Compare against 18 x 11 x 11 inches. If any dimension is larger, ask Delta Reservations whether it fits the aircraft on your flight.
4. Check the fit with your pet inside. Your pet must be able to move around without touching or sticking out of the sides, according to Delta.
5. Check ventilation and leak-proofing. Count the mesh sides, and add an absorbent liner.
6. Call Delta Reservations early. Delta uses a first-come, first-served policy with a limit on total pets per flight.
7. Arrive early and go to the Special Service Counter, where Delta checks the kennel and collects the pet fee.

How many pets Delta allows per cabin

Delta Air Lines limits in-cabin pets per flight, not per passenger. These are the published caps as of September 2026:

Delta's travel-agent page adds one exception: Delta may accept in-cabin pets in international Business and First Class when the aircraft is not configured with flat-bed seats. The consumer page does not mention this, so confirm it with Reservations.

Seats you cannot choose with a pet

Delta's Pet Travel Overview says passengers with an in-cabin pet may not select:

• Bulkhead seats
• Emergency exit rows
• Seats marked "no stowage"
• Flat-bed or Delta One seats
• Rows 46–51 on the Airbus A330-200
• Rows 54–59 on the Airbus A330-300
• Center seats on the Boeing 757-200

Delta's travel-agent page also lists the Boeing 737-900ER, Row 1 and window seats in First Class (no under-seat stowage) and Delta Premium Select seats. When the two pages differ, plan around the longer list.

Delta in-cabin pet fees in 2026

Delta collects the in-cabin pet fee each way at check-in. The fee depends on the date your ticket was issued, according to Delta's Pet Travel Overview (checked September 2026):

• U.S., Canada, Puerto Rico, U.S. Virgin Islands: $150 USD/CAD for tickets issued on or after April 8, 2025 ($95 for tickets issued before that date).
• International: $200 USD/CAD/EUR.
• Brazil: $200 USD for tickets issued on or after April 8, 2025 ($75 before that date). Delta separately says pets originating in Brazil are not accepted in the cabin.

Delta says these fees are set by the contract of carriage in effect when the ticket is issued. The kennel counts as your pet's space, and you may still bring 1 personal item or 1 carry-on.

Age, species and documentation rules that affect your carrier booking

A carrier that fits under the seat is only one part of the booking. Delta's 2026 overview sets these additional in-cabin rules:

• Species: small dogs, cats and household birds. Delta's agent page says household birds may fly in the cabin only on domestic U.S. flights.
• Minimum age: 8 weeks for domestic travel, 15 weeks for travel to the European Union, and for pets entering the U.S. from abroad, 6 months for dogs and 16 weeks for cats.
• Shared kennels: a mother cat or dog may travel with her un-weaned litter aged 8 weeks to 6 months, and 2 pets of the same breed and size in that age range may share 1 kennel and pay as 1 pet.

Delta's older Requirements & Restrictions page gives a different age: it cites USDA rules requiring animals to be at least 10 weeks old and fully weaned for domestic travel. That page mainly covers health certificates for cargo and checked pets, but the conflict is another reason to confirm with Delta directly.

Dogs flying into the United States

The U.S. Centers for Disease Control and Prevention (CDC) is the primary authority for dogs entering or returning to the United States. The United States Department of Agriculture Animal and Plant Health Inspection Service (USDA APHIS) confirmed this on its Travel With a Pet page (last modified March 20, 2026). Under CDC rules effective August 1, 2024, dogs entering the U.S. must appear healthy, be microchipped, be at least 6 months old and travel with a CDC Dog Import Form receipt. Extra documents depend on where the dog was vaccinated and whether it has been in a high-risk rabies country in the past 6 months. Delta repeats these rules on its own pet travel page.

Delta's 2026 overview also flags New World Screwworm (NWS) inspection rules. From August 3, 2026, all dogs entering Mexico need a New World Screwworm Inspection Certificate completed by a USDA-accredited veterinarian no more than 5 days before arrival, and Delta checks it at check-in.

Destinations where Delta does not allow pets in the cabin

No carrier size will get a pet into the cabin on these routes. Delta's Pet Travel Overview (2026) lists travel to or from Australia, Barbados, Hong Kong, Iceland, Jamaica, New Zealand, South Africa, the United Kingdom and the United Arab Emirates. It also bans pets originating in Brazil, Colombia or the Dominican Republic, and pets on flights to Hawaii. Delta's travel-agent page also lists Ireland, which the consumer page does not.

What about larger kennels, checked pets and cargo?

If your pet is too big for an under-seat carrier, the in-cabin dimensions above do not apply. Delta's travel-agent Pet Policies page says Delta Cargo has an embargo on all pet-in-hold (AVIH) bookings with no end date. Pets in the hold are accepted only for active U.S. military and U.S. State Department Foreign Service Officers with transfer orders, on flights under 12 hours. Those kennels must be rigid USDA-compliant shipping crates, and Delta's older requirements page lists sizes from the SML/100 series (21 x 15 x 16 inches) up to the GIANT/700 series (48 x 32 x 35 inches, cargo only).

Delta's travel-agent page also says Delta does not accept snub-nosed or pug-nosed dogs and cats as checked baggage. This restriction does not apply to in-cabin travel in a compliant carrier.

Delta pet carrier rules vs. Animal Passport: not the same thing

Delta's kennel rules, the CDC Dog Import Form and USDA APHIS health certificates are official travel requirements. Animal Passport is a different kind of product. It is a digital animal and livestock passport that identifies animals by muzzle biometrics, since a nose print is unique like a fingerprint.

• What Animal Passport does: it captures a nose print on a phone and links it to a record of owner, breed, estimated age, body condition and vaccination history. Age is estimated from a dental photograph with a confidence score, and body condition is scored 1–5 from a side-profile photo.
• Where it has been used: during livestock flood rescue in Pakistan in August 2025, it helped farmers reclaim animals after paper tags washed away.
• What it is not: it is not a government-issued travel document, an airline pet booking, a CDC Dog Import Form or a USDA health certificate. It does not provide veterinary diagnosis or legal advice.

For flying with a pet on Delta, follow Delta, CDC and USDA APHIS rules. For more on animal identification and records, see the Animal Passport blog.

Bottom line

As of September 2026, the practical answer to "what size pet carrier does Delta allow?" is a soft-sided, leak-proof carrier no larger than 18 x 11 x 11 inches, ventilated on at least 3 sides (4 for international), that fits fully under the seat in front of you with room for your pet to move. Book early by phone, give Delta your exact kennel measurements, avoid restricted seats, and budget $150 each way domestically or $200 internationally. Airline policies change often, so check Delta's Pet Travel Overview again a few days before departure.