Your dog is not cold, and a shirt will not make them cooler either
Search for summer dog clothes and you will be told, on the same page, that a shirt keeps a dog cool and that clothing makes a dog overheat. Both claims are half true, which is worse than either being wrong. A dog does not sweat through its skin the way you do. It cools by panting and by radiating heat through the belly, the paw pads and the ears. Anything you put on the torso interferes with the third of those, a little.
So why do so many dogs end up in a cotton tank between June and September? Because owners are solving a different problem than the one the marketing describes. Three real problems, actually - hair on the furniture, skin that needs covering, and sun on a thin coat. A shirt is a genuinely good answer to all three. It is a poor answer to "my dog is hot".
What a summer shirt actually does
It catches shed hair before your sofa does
This is the honest reason most people buy one. A double-coated dog in July drops hair continuously, and every surface it touches collects some. A close-fitting cotton tank intercepts a good share of it. The hair ends up in the wash instead of woven into upholstery, where it is far harder to remove.
It does not stop shedding. Nothing worn on the outside changes what the follicle is doing. It just changes where the hair lands.
It covers skin that should not be licked or scratched
- Hot spots - a moist dermatitis patch heals faster when the dog cannot get at it. For mild cases a soft shirt is more humane than a plastic cone, and dogs tolerate it far better.
- Post-clip skin - a shaved flank after an ultrasound or a mat removal is exposed and itchy. A layer over it stops the scratching cycle.
- Healing incisions - only with your vet's agreement, and only once the wound is closed. A shirt is not a surgical recovery suit.
It blocks some sun on a thin or pale coat
Dogs with pink skin under a sparse white coat do get sunburned, most often along the back and the bridge of the nose. Fabric over the back is a straightforward barrier. It does nothing for the nose, the ears or the belly, which is where you still need shade and timing.
What it does not do
It does not cool your dog down
You will read that a shirt "traps cool air" or "reflects heat". On a dog, in real conditions, a dry layer of cotton is at best neutral and at worst a small insulator. If your dog is panting hard, the shirt is not the fix - shade, water and a cooler surface are.
There is one exception, and it is a different product: a cooling mat or a wet cooling bandana works by evaporation. A dry cotton tank does not evaporate anything.
It does not replace grooming
A shirt on an ungroomed double coat traps loose undercoat against the skin. That is how you get matting in the armpits and along the flanks. The shirt only works on a coat that is already being brushed.
Cotton, polyester, or neither
- Cotton - breathes, washes at any temperature, shrinks in a hot dryer. The default choice for summer.
- Polyester and blends - hold their shape and dry fast, but sit warmer against the skin. Better for a rain layer than a July tank.
- Fleece - a winter fabric. It has no place on a dog in summer, whatever the label says.
Getting the size right, which is where most orders go wrong
Dog clothing sizing is not standardised at all, and most of what sells online is cut on Asian sizing - typically one to two sizes below what the same letter means on a US label. A "large" from one seller is a "medium" from another.
- Measure the chest girth - a soft tape all the way around the deepest part of the ribcage, just behind the front legs. This is the measurement that decides whether a shirt fits.
- Measure the back length - base of the neck to the base of the tail. This decides whether it looks right.
- Compare to a shirt your dog already wears - lay it flat and measure it. This beats any chart, because you know that one fits.
- Between two sizes, go up - a loose tank is a mild annoyance. A tight one is coming off within the hour and will not go back on.
Signs it is too small
- The neckline flattens the shoulders - your dog will walk strangely, low and hesitant, before it protests.
- You can see the outline of the ribs through the fabric - it is stretched, and it will chafe in the armpits.
- The dog stops moving - the classic frozen stance. Nine times out of ten it is fit, not fabric.
Introducing a shirt to a dog that has never worn one
- Put it on for two minutes, indoors, then take it off and do something ordinary.
- Repeat before a meal, not before a walk. You want the shirt to predict food, not restraint.
- Build up to twenty minutes over several days.
- Only then wear it outside, where there is far more to react to.
A dog that freezes on day one is not refusing clothes forever. It is reacting to an unfamiliar pressure on the shoulders, and that fades with repetition.
Common Mistakes
- Buying the size the letter suggests - measure. Nearly every return on dog apparel is a sizing return.
- Leaving it on all day in heat - shirt off for the midday walk and for sleeping in the sun. On for the couch and the car.
- Putting a shirt on a wet dog - cotton holds water against the skin and keeps it cold and damp. Dry the dog first with a drying robe, then dress it if you want to.
- Using a shirt instead of a cone on a fresh wound - ask your vet. A shirt is for mild irritation, not for a surgical site.
- Hot tumble drying cotton - it shrinks by a full size. Air dry.
Frequently Asked Questions
Will a shirt make my dog overheat?
A light cotton tank on a dog at rest, indoors or in shade, is unlikely to. A dog running in direct sun in any layer can overheat. Judge by the dog: heavy panting, bright red gums or reluctance to move means the layer comes off and the walk ends.
Can my dog wear it all day?
For hair control on the furniture, yes, as long as you check the skin underneath daily for rubbing and matting. In a heatwave, no.
Does a shirt stop shedding?
No. It changes where the hair goes, not how much comes out. Brushing changes how much comes out.
My dog freezes when I put it on. Is it the wrong size?
Check the fit first, because that is the most common cause. If the fit is right, it is novelty, and a week of short sessions before meals usually resolves it.
Cotton or polyester for summer?
Cotton. It breathes better and washes more easily. Save synthetics for rain layers.
What about cats?
Most cats tolerate clothing far worse than dogs, and a cat that cannot groom normally will get distressed. Unless a vet has asked you to cover something, leave cats undressed.
The Bottom Line
Buy a summer shirt to keep hair off your furniture, to cover skin your dog should not be licking, or to shade a pale back. Do not buy one to cool your dog down - that is what shade, water and a cooling mat are for.
If that is what you are after, our All-Star Basketball Jersey is a plain cotton tank in black or red, sleeveless so the front legs stay free. It runs one to two sizes small, so measure the chest and order up. For colder months, the same job is done by the knit sweater range, and there is more on fit in our guide to measuring your dog for clothes. The rest of the wardrobe lives in Dog & Cat Apparel.