You felt it on this morning's walk. Not cold exactly, but a change. The grass held the damp a little longer, your breath showed for a second under the streetlight, and your dog paused at the door in that way they do when the air smells different. Summer has not gone anywhere yet. But it has started to think about leaving.
Which brings up the question every UK dog owner asks around this time of year: does my dog actually need a jumper, or is it just very cute? Here is the honest, practical answer.
The quick answer
Most healthy medium and large dogs with thick double coats do not need a jumper for a normal British autumn day. But small breeds, thin-coated breeds, puppies, senior dogs, and dogs that feel the cold genuinely benefit from a jumper once temperatures drop below around 10°C, and almost all of them appreciate one below 7°C, especially when it is wet or windy. If your dog shivers, hunches, lifts their paws or rushes to get home, that is your sign, whatever the thermometer says.
Now let's make that useful for your specific dog.
Which dogs feel the cold most?
Your dog's coat is their first layer, and not all coats are equal. The dogs who most often need a helping layer are:
- Small and toy breeds (Chihuahuas, Miniature Dachshunds, Yorkshire Terriers, Italian Greyhounds). Less body mass means they lose heat faster, and they sit closer to cold, damp ground.
- Thin or single-coated breeds (Whippets, Greyhounds, Staffies, Boxers, French Bulldogs). Little to no insulating undercoat.
- Puppies, who cannot regulate their body temperature as well as adults.
- Senior dogs and dogs with arthritis, whose joints stiffen in the cold and who move less to generate heat.
- Dogs that are unwell, underweight, or recently clipped.
- Lean, low-slung dogs like Dachshunds, whose tummies skim the wet grass.
By contrast, thick double-coated breeds built for cold climates (Huskies, Malamutes, Samoyeds, Newfoundlands, most Spitz types) are usually happier without a jumper and can overheat in one. When in doubt, watch the dog, not the fashion.
At what temperature does a dog need a jumper?
There is no single magic number, because wind, damp and your dog's size all matter. As a rough UK guide:
- Above 12°C: most dogs are fine in just their own coat.
- 7°C to 12°C: small, thin-coated, young, senior or slim dogs will be more comfortable in a jumper, particularly for slower sniffy walks where they are not running to stay warm.
- Below 7°C: add a layer for vulnerable dogs, and consider a waterproof coat over the top if it is wet.
- Below 0°C: keep walks shorter for at-risk dogs, and layer a warm jumper under a windproof, waterproof coat.
Wind chill and rain change everything. A damp 8°C morning feels far colder to a small dog than a dry, still one. Trust what you see on the walk.
Signs your dog is cold
Dogs are stoic, so the signals are quiet. Look for:
- Shivering or trembling
- A hunched back, tucked tail and lowered head
- Lifting paws off the cold ground, or reluctance to walk on
- Slowing down, or steering you back towards home
- Whining, or seeking out warm spots and curling up tightly at home
If you see these, a jumper is not a gimmick. It is genuine comfort, and for older dogs it can make the difference between a walk they enjoy and one they endure.
Jumper or coat? What is the difference
They do different jobs, and a lot of dogs use both across the season.
A jumper is a warmth layer. It traps heat close to the body and is perfect for cool, dry days, chilly houses, the car, the vet's waiting room, and evenings on the sofa when the heating is not on yet. A good knit is soft, breathable and easy to move in.
A coat is a weather layer. Its job is to block rain and wind. On a truly wet, blustery day, the ideal set-up for a cold-sensitive dog is a warm jumper underneath and a waterproof coat over the top, exactly as you would layer yourself.
If you want the full run-down on wet-weather layers, our guide to the best waterproof dog coats UK 2026 covers coats in detail. This guide is about the warm layer underneath.
How to choose the right dog jumper
Four things matter far more than colour.
1. Fit
Measure your dog's back length from the base of the neck to the base of the tail, and the widest part of the chest. Check these against the maker's size guide rather than guessing from weight alone, because two 8kg dogs can be very different shapes. If your dog is between sizes, size up. A jumper should be snug but never tight: your dog needs to walk, squat and stretch freely, and you should be able to slide two fingers under the neckline.
2. Material
Natural fibres like alpaca and wool are wonderfully warm for their weight, breathable, and naturally a little water-resistant. Alpaca in particular is prized for being soft rather than itchy and for being gentle on sensitive skin. Cotton jumpers are lighter, brilliant for indoor wear and milder days, and easy to machine wash. Fleece is cosy, light and quick-drying.
3. Freedom of movement and harness access
Look for a jumper that leaves the legs and belly free to move and, ideally, has a leash or harness opening so you can wear a harness underneath and clip on without faff.
4. Care
Check the label. Many knits, especially alpaca, are hand-wash only and should be dried flat to keep their shape, while cotton and fleece are usually machine washable. Pick what suits your life.
Our favourite jumpers for the turn of the season
A few Duke & Milo picks, from properly cosy to everyday light:
- The "Holiday" Handmade Alpaca Wool Dog Jumper (£45): our warmest, most-loved knit. Hand-made in Peru by Alqo Wasi from a soft alpaca-wool blend (50% alpaca, 45% acrylic, 5% wool), with a ribbed turtleneck and a handy leash opening. Soft rather than itchy, light for its warmth, and genuinely beautiful. The colourful "Holiday" is part of a wider range of handmade alpaca knits, so there is a design and size for most dogs, though the good sizes do tend to go first.
- The Cosy Jumper by House of Paws (£14.99): a fleece-backed, knitted-underside jumper with an opening for easy harness and collar access. Machine washable and a great-value everyday warm layer. It sizes small, so consider sizing up.
- The Blinky Jumper by The Painter's Wife (£16.99): a soft 100% Portuguese-cotton knit, ideal for indoor wear and milder autumn days, or as a light layer under a coat. Art-led and characterful, named after the painter Blinky Palermo.
You can browse the full dog clothing and apparel collection to see the complete range of jumpers and coats.
Don't forget the paws
Cold, wet pavements and the first grit of the season are hard on paw pads. A quick rub of a natural balm keeps them supple and protected. Our CALM & CARE Paw Balm (£7) is handmade in the UK with lavender and chamomile, and doubles as a calming balm for the darker, fireworks-season evenings ahead.
Frequently asked questions
Do dogs really need jumpers, or is it just for looks?
For thick double-coated breeds, a jumper is mostly for looks and they may not need one at all. For small, thin-coated, young, senior or slim dogs, a jumper provides real warmth and comfort once it turns cold, and can make walks far more enjoyable.
At what temperature should I put a jumper on my dog?
As a guide, consider a jumper for vulnerable dogs below about 10°C, and for most cold-sensitive dogs below 7°C. Wind and rain make it feel colder, so watch your dog for shivering, hunching or reluctance to walk rather than relying only on the thermometer.
How do I know what size jumper to buy?
Measure back length from the base of the neck to the base of the tail, and the widest part of the chest, then match to the maker's size guide. If your dog is between sizes, size up. The jumper should be snug but allow free movement.
Is alpaca wool good for dogs with sensitive skin?
Alpaca fibre is loved for feeling soft and smooth rather than scratchy, which makes it gentle. As our jumpers are an alpaca blend, we would still introduce it gradually if your dog has particularly sensitive skin, and check for any irritation.
Can my dog wear a harness under a jumper?
Yes. Choose a jumper with a leash or harness opening, like our alpaca knits and the Cosy Jumper, so you can wear the harness underneath and clip on the lead through the opening.
Should my dog wear a jumper and a coat together?
On cold, wet, windy days, yes. Use a warm jumper as the base layer for heat, with a waterproof, windproof coat over the top for weather protection, just as you would layer up yourself.
Free UK delivery over £30.