The best clothes for French Bulldogs in hot weather are light, breathable and loose at the neck: a wet mesh cooling shirt for short outings in dry heat, a UPF 50 rash shirt for sun and beach time, and a thin stretch cotton tee for lounging in the shade. Skip anything heavy, tight or non-breathable, size for that deep Frenchie chest, and remember that on the hottest days the best outfit is staying inside with the air con.
Key takeaways
- French Bulldogs cool mainly by panting, and their airways make that harder, so summer clothes must never add heat or press on the neck or chest.
- Most Frenchies wear a Medium (57–67 cm chest), but broad, chunky Frenchies often need a Large. Measure the chest just behind the front legs.
- Pick by job: a wet cooling shirt for heat, a UPF 50 rash shirt for sun, a light stretch cotton tee for shade and home.
- Pied, white and pink-skinned Frenchies need extra care in the sun. A UPF 50 shirt helps reduce UV exposure on the back and belly.
- No shirt replaces shade, water and staying home in the heat of the day. Heatstroke is an emergency: get to a vet.
Why do French Bulldogs struggle in hot weather?
Dogs don't sweat like we do. They have only a small number of sweat glands, mostly in their paw pads, and panting is their main way of controlling body temperature.1 For a flat-faced breed, that is the problem in a nutshell.
French Bulldogs are brachycephalic: a short skull and flattened face that often comes with obstructions in the upper airway. The result is brachycephalic obstructive airway syndrome, or BOAS. RSPCA Australia describes BOAS as a lifelong and often progressive disorder, and notes that brachycephalic dogs have an increased risk of heat stress and heatstroke and may be unable to exercise normally, especially in warmer and more humid weather.2
The numbers are sobering. A Royal Veterinary College (RVC) VetCompass study of 2,781 French Bulldogs under UK vet care found Frenchies had around 31 times the odds of a BOAS diagnosis compared with other dogs, and around 42 times the odds of stenotic (narrowed) nostrils.3 Another RVC study of more than 900,000 dogs named the French Bulldog as a breed at higher risk of heat-related illness, along with dogs carrying extra weight for their breed.4
BOAS is also easy to miss at home. University of Cambridge researchers testing 89 Frenchies found that 60% of owners didn't recognise BOAS in dogs that were clinically affected.5 That cute snore may be your dog working hard to breathe, so assume your Frenchie has little cooling capacity to spare.
Humidity makes it worse. Vets note that heatstroke signs can appear when temperature and humidity are only moderately raised,1 and RSPCA Australia flags warm, humid places with poor airflow as a particular risk.6
For the full set of non-clothing tips (walk times, hot footpaths, cars, cool spots at home), see our guide on how to keep a French Bulldog cool in summer. This article sticks to the wardrobe.
Why are clothes for French Bulldogs so hard to fit?
A Frenchie is a small dog wearing a big dog's chest. The RVC study above found a typical Frenchie weighs about 12.5 kg,3 yet the breed's deep barrel chest, short back and thick neck mean "small dog" sizing rarely works. Size by length and the chest gets squeezed; size by chest and the shirt can flap down the back.
The neck deserves special respect. In a Cambridge study of 604 Pugs, French Bulldogs and Bulldogs, neck girth and neck length (relative to body size) were significantly associated with BOAS in Frenchies.7 That doesn't mean a shirt causes airway problems, but it is a good reminder: for a dog that already breathes through a narrow straw, nothing should ever sit snug around the throat.
What size shirt does a French Bulldog wear?
From our dog shirt size by breed guide, here's what our size charts say for Frenchies:
- Usual size: Medium. Chest 57–67 cm, neck 41–51 cm, back length 34 cm.
- Broad or chunky Frenchies often need a Large. Chest 65–75 cm, neck 46–56 cm, back length 37 cm.
- Between sizes? Size up. Our shirts are 190gsm cotton with 5% spandex, so they stretch, but in summer roomy beats snug every time.
To measure, stand your dog up and run a soft tape around the widest part of the chest, just behind the front legs. Measure over the fur, snug but not tight. Chest is the number that matters most for a Frenchie; check the neck measurement second. And if you still get it wrong, your first size exchange is free.
What fabrics are best for Frenchie summer clothes?
In summer, a shirt should either actively help (cooling, sun protection) or be so light your dog forgets it's there. Anything else is insulation.
Breathable mesh cooling shirt: for heat
A French Bulldog cooling shirt works like portable sweat. You soak it, wring it out and put it on; as the water evaporates it draws heat away from your dog's body.8 Re-wet it as it dries.
The honest fine print: evaporative cooling works best in dry heat. On muggy days evaporation slows and cooling vests become less effective,8 and they are not a replacement for careful, limited exercise in hot weather.8 In Perth's dry heat it earns its keep; on a sticky Brisbane afternoon it's a small helper, not a plan. One more important point: if you ever suspect heatstroke, take the shirt off. Vets advise against wrapping an overheated dog in wet cloths because they can trap heat.1
Light stretch cotton tee: for shade and home
A thin stretch cotton tee suits indoors, the shady verandah or a cool evening. It won't cool your dog; its job is simply not to add heat.
UPF 50 rash shirt: for sun and beach
A rash shirt is about UV, not heat. Cancer Council Australia rates UPF 50 fabric as "excellent protection", blocking about 98% of UV radiation.9 The same source notes that fabric protects less when it is stretched or wet, and that you should choose the correct size for the wearer,9 which is one more reason not to squeeze a Frenchie into a too-small shirt. Our Red Gingham UPF 50 rash shirt covers the back and sides, the parts of your dog that face the sky.
Australia has some of the highest UV levels in the world, and UV can be high even on cool, overcast days.10 So the rash shirt is useful well beyond the beach.
What to avoid in summer
- Heavy or thick fabrics: fleece, hoodies, knitted jumpers and padded jackets belong in July.
- Tight fits: anything that pulls across the chest or sits close to the throat.
- Non-breathable synthetics: plastic-feeling fabrics, raincoats and coated materials that trap warm, damp air against the skin.
- Costumes with extras: hoods, scarves and bows around the neck.
What about colour? It's more nuanced than "dark is hot". Darker fabrics actually absorb more UV, so they give more sun protection than pale ones of the same type.9 We couldn't find good evidence that fabric colour on its own overheats dogs, so focus on weight, breathability and fit first.
Built for the Frenchie chest, made for the Aussie summer
Breathable mesh cooling shirts you soak, wring and wear, in sizes XS–XXL and bold original prints.
Do pied, white and fawn Frenchies need sun protection?
Yes, more than most. RSPCA South Australia warns that dogs with white, thin or no hair can suffer severe sunburn, and that pure white dogs are also at risk of skin cancers.11 The areas to watch are the nose, belly, groin, ear tips and anywhere the fur is thin.11
Pied (white with patches) and cream Frenchies are the obvious ones, but fawn and brindle Frenchies can still have a pink, lightly furred belly, and plenty love sunbaking belly-up on the deck.
For Frenchie sun protection, combine:
- Shade and indoor time in the middle of the day.
- A UPF 50 rash shirt when you're out in the sun, which helps reduce UV exposure on the back, sides and part of the belly.
- A pet-safe sunscreen on exposed bits like the nose and ear tips (ask your vet which one).
A shirt helps reduce UV exposure; it doesn't make your dog sun-proof or prevent skin cancer. If you notice red, scabby or crusty patches, or a sore that won't heal, see your vet.
How do I know if my Frenchie's shirt is too tight or too hot?
Do a quick check every time a shirt goes on, and again a few minutes later.
Signs it's too tight
- You can't easily slide two fingers under the neckline or around the chest.
- The fabric pulls tight across the chest or rides up into the armpits.
- Red marks or rubbing under the front legs or around the neck when it comes off.
- Your dog walks stiffly, sits down and refuses to move, or keeps trying to scratch it off.
Signs it's too hot (take it off now)
- Panting harder or faster than usual for the activity.
- Louder, noisier breathing than normal.
- Seeking cold floors, lying flat, or slowing down on a walk.
Know where "too hot" ends and an emergency begins. RSPCA Australia lists constant panting, rapid breathing and heart rate, drooling, vomiting, weakness, confusion, muscle tremors, seizures and collapse as signs of heatstroke.6 If you see these, remove all clothing, start cooling your dog with room-temperature or cool water on the fur and skin, keep the air moving, and seek veterinary attention immediately.6
When should you NOT dress your French Bulldog?
Leave the clothes off when:
- It's genuinely hot outside. On scorching days the right move is home, air con and a frozen treat, not a better shirt.
- Your dog is exercising hard. Fetch, zoomies and long walks generate heat a shirt can't fix.
- It's humid and the cooling shirt can't evaporate. A wet shirt that won't dry is just a damp blanket.
- You're leaving them unsupervised.
- Your dog is distressed by it. Freezing, hiding or frantic scratching means no.
- There's a skin issue, wound or recent surgery, unless your vet suggests covering it.
- Your dog shows any sign of heat stress. Clothes off first, then cool down.
A Frenchie summer wardrobe for every situation
Here's how we'd put together French Bulldog outfits for a typical Aussie summer. Browse the full range of French Bulldog clothes to fill the gaps.
| Situation | Best choice | Why | Watch out for |
|---|---|---|---|
| Early morning or evening walk | Wet mesh cooling shirt, or nothing | Evaporative cooling on the way home as the day warms up | Re-wet when dry; less useful on humid mornings |
| Beach or park in the sun | UPF 50 rash shirt | Helps reduce UV on the back and sides | Still needs shade, fresh water and a short visit |
| At home or in the shade | Light stretch cotton tee, or nothing | Comfort and style without adding much warmth | Remove if panting increases |
| Night (air-conditioned room) | Light cotton pyjamas | Keeps a chilly, short-coated dog comfy under the air con | Skip if the room is warm |
| Hot middle of the day | Nothing; stay inside | No shirt makes a hot day safe for a flat-faced breed | Watch for heat stress signs even indoors |
At night, short-coated Frenchies can actually get chilly in an air-conditioned bedroom, so light stretch cotton dog pyjamas work well there. If the room isn't cooled, skip them. After the beach, rinse salt and sand out of the rash shirt, then machine wash cold and air dry.
FAQs
What size clothes does a French Bulldog wear?
Most French Bulldogs wear a Medium, which fits a 57–67 cm chest. Broad, chunky Frenchies often need a Large (65–75 cm chest). Measure around the widest part of the chest just behind the front legs, and size up if you're between sizes.
Is it cruel to put clothes on a French Bulldog in summer?
Not if the clothes have a purpose and your dog is comfortable. A wet cooling shirt or a UPF 50 rash shirt can help in the right conditions. Heavy, tight or unnecessary clothes on a hot day are a bad idea for any flat-faced breed.
Do cooling shirts work in humid weather?
Less well. Cooling shirts rely on evaporation, which slows down when the air is humid. On muggy days rely on air con, shade, water and staying in.
Does a French Bulldog need sun protection?
Many do, especially pied, white and cream Frenchies, or any dog with pink skin and thin fur on the belly, nose or ears. Combine shade, a UPF 50 shirt and a vet-recommended pet sunscreen on exposed spots. See your vet about any red, crusty or non-healing skin.
Can my Frenchie wear a cooling shirt all day?
No. Use it for short, supervised outings and take it off once it dries or your dog is back inside. Never leave a dog alone in any shirt, and take it off immediately if you suspect heat stress.
References
- VCA Animal Hospitals, "Heat Stroke in Dogs". https://vcahospitals.com/know-your-pet/heat-stroke-in-dogs
- RSPCA Australia Knowledgebase, "What do I need to know about brachycephalic dogs?". https://kb.rspca.org.au/knowledge-base/what-do-i-need-to-know-about-brachycephalic-dogs/
- O'Neill DG et al. (Royal Veterinary College), "French Bulldogs differ to other dogs in the UK in propensity for many common disorders: a VetCompass study", Canine Medicine and Genetics, 2021. https://pmc.ncbi.nlm.nih.gov/articles/PMC8675495/
- Hall EJ, Carter AJ, O'Neill DG, "Incidence and risk factors for heat-related illness (heatstroke) in UK dogs under primary veterinary care in 2016", Scientific Reports, 2020. https://pmc.ncbi.nlm.nih.gov/articles/PMC7303136/
- Liu NC et al. (University of Cambridge), "Characterisation of Brachycephalic Obstructive Airway Syndrome in French Bulldogs Using Whole-Body Barometric Plethysmography", PLOS ONE, 2015. https://pmc.ncbi.nlm.nih.gov/articles/PMC4469695/
- RSPCA Australia Knowledgebase, "How can I protect my dog from heatstroke?". https://kb.rspca.org.au/knowledge-base/how-can-i-protect-my-dog-from-heatstroke/
- Liu NC et al. (University of Cambridge), "Conformational risk factors of brachycephalic obstructive airway syndrome (BOAS) in pugs, French bulldogs, and bulldogs", PLOS ONE, 2017. https://pmc.ncbi.nlm.nih.gov/articles/PMC5538678/
- Preventive Vet, "How to Keep Your Dog Cool During Hot Weather". https://www.preventivevet.com/dogs/how-to-keep-your-dog-cool
- Cancer Council Australia, "Sun protective clothing". https://cancer.org.au/cancer-information/causes-and-prevention/sun-safety/be-sunsmart/sun-protective-clothing
- Cancer Council Australia, "UV Index". https://www.cancer.org.au/cancer-information/causes-and-prevention/sun-safety/uv-index
- RSPCA South Australia, "The must-know steps to keeping your white pet safe from dangerous sunburn". https://www.rspcasa.org.au/protect-white-pets-from-sunburn/