Travelling With a Flat-Faced Dog: Heat, Flights and the Airline Bans

A bulldog, a pug or a French bulldog can travel well. But a flat face changes the rules of a journey more than any other feature a dog can have. It decides which airlines will carry your dog and where, how hot a day is too hot, and what kind of car and hotel room you should be looking for. This guide draws on the veterinary research and each airline's own pages, read in October 2026.

Why a Flat Face Matters on a Journey

A short-nosed, or brachycephalic, dog has the same nasal passages, sinuses and palate as any other dog, packed into a much smaller space. The American Veterinary Medical Association explains what follows: narrow nostrils, a soft palate that is too long and a narrowed windpipe, so the dog breathes less efficiently and struggles to cool down when it is excited, stressed or hot. Under strain the airway can partly collapse, and a dog that cannot pant freely cannot shed heat.

The largest study of the question looked at the veterinary records of more than 900,000 dogs in Britain. Published by Emily Hall, Anne Carter and Dan O'Neill in Scientific Reports in 2020, it found that flat-faced dogs had about twice the odds of heat-related illness of dogs with an ordinary muzzle, and that about one dog in seven treated for it died. Compared with the Labrador, the Royal Veterinary College reported the Bulldog at fourteen times the risk, the French Bulldog at six times and the Pug at three times. Being heavy for the breed raised the risk by almost half again.

In a heat chamber study of 60 brachycephalic and 45 other dogs, M. Davis found flat-faced dogs less able to hold a normal temperature, but also that body condition was a greater determinant of body temperature than breed. A lean pug is a safer traveller than a plump one, and that is the one part of the problem an owner can change before a trip.

What the Air Travel Figures Show

In July 2010 the US Department of Transportation published figures showing that about half of the 122 dog deaths on airline flights over the previous five years involved short-faced breeds. Twenty-five of the dead were English bulldogs and eleven were pugs, the only two breeds in double figures. The AVMA notes that this is a small number against the hundreds of thousands of animals that fly each year, but explains the risk: in the hold there is nobody to watch a dog that starts to struggle, and the hold can heat up while the aircraft sits on the ground with its air systems turned down. The airlines took note.

The Airline Rules Side by Side

In Europe the pattern is now almost uniform: a flat-faced dog may fly in the cabin if it fits the weight limit, and not in the hold. KLM refuses most snub-nosed breeds in the hold, allows them in the cabin, where dog and bag together may weigh no more than 8 kg, and will carry them as cargo. Air France says snub-nosed dogs are permitted in the cabin but not in the hold, and its pet page sets the cabin limit at under 8 kg with the carrier. Lufthansa has refused snub-nosed dogs in the hold since 1 January 2020, and LOT bans them below deck too, applying the rule to crossbreeds and to any dog with a short muzzle, while still offering cargo. Our guide to Lufthansa lists the breeds it covers.

North America has gone further, partly because the big American airlines have closed the hold to ordinary passengers. American checks pets into the hold only for US military and State Department staff on official orders, and United no longer checks pets in at all, so for everyone else a dog flies in the cabin or not with them. Delta keeps the hold for the same military and diplomatic travellers and excludes pug or snub-nosed dogs even then, and Delta Cargo refuses them at all times. Its list runs well beyond the obvious, to the Cavalier King Charles Spaniel and the Staffordshire Bull Terrier. Air Canada will not put a snub-nosed dog in the baggage compartment, and Alaska Airlines refuses them in the hold and, from 31 July to 30 September 2026, would not take French or English bulldogs below deck even as cargo.

A pug, a Boston terrier or a small French bulldog that makes the cabin weight can still fly on most of these airlines, and the cabin is where it should be. A bulldog, a boxer or a big French bulldog cannot fly with you on any of them, and cargo, where an airline still offers it, means the same hold without you.

Before You Book: Know How Your Dog Breathes

The most useful thing you can learn before any long trip is how well your own dog breathes, and in Britain there is a formal way to find out. The Respiratory Function Grading Scheme, run by the Royal Kennel Club and the University of Cambridge, has trained vets grade a dog for brachycephalic obstructive airway syndrome from the age of twelve months. Grade 0 means no signs, grade 1 some breathing noise that does not affect exercise, grade 2 moderate signs that may need treatment, and grade 3 severe signs that need a full veterinary examination. A grade 2 or 3 dog is not one to put through a long flight or a summer road trip, and the Cambridge BOAS Research Group runs a clinic for dogs with the condition at the university's veterinary hospital.

The AVMA's own advice for a flat-faced dog that has to fly is to keep it at a healthy weight, get it used to its carrier well before the trip, line the carrier with something thin rather than a thick blanket it can bury its nose in, and not to tranquilise it, because sedation increases the risk. Where you have the choice, book early morning or late evening flights in warm months and avoid long layovers. If the dog is too big for the cabin, the honest answer is often not to fly it: a train, a ferry or a car journey planned around the heat will usually be kinder. Our guides to dogs on trains and coaches and training your dog to travel cover the alternatives and the carrier work.

On the Ground: Cars, Hotels and Walks

Much of the danger lies on the ground rather than in the air, and flat-faced dogs are at risk in situations other dogs shrug off. A 2020 study of what triggers heatstroke found that bulldogs, pugs and other flat-faced dogs were at increased risk simply sitting outside in hot weather, and particularly at risk in hot cars. Dan O'Neill of the Royal Veterinary College warned that such dogs often suffer in hot weather, during exercise or even on a short car journey. In the car that means air conditioning reaching the back seat, not a window left down, and never leaving the dog in a parked car on a warm day. Our guide to driving with your dog covers the rest.

On walks, our heat guide suggests taking about four degrees off every temperature threshold for a flat-faced dog. Plan the proper walks for dawn and dusk, keep them gentle, and carry water. When you choose where to stay, air conditioning in the room is not a luxury for these breeds but the place your dog will spend the hottest hours, and a ground floor room or a lift spares a dog that labours on stairs. Ask before you book; our list of questions to ask any hotel includes the ones that matter here. A flat-faced dog can see a great deal of the world, with an owner who plans each journey around its breathing.