You open the front door, and your dog plants all four feet. Or you make it two blocks before the shivering starts and they turn for home. Many dogs feel the cold far more than we realize, and a good coat can turn a miserable winter walk into a happy one.

But not every dog needs one, and the wrong size can be almost as bad as none at all. This guide helps you decide whether your dog needs a winter coat, shows you how to measure a dog for a coat in three simple steps, and explains what a good fit looks like, so you order the right size the first time.

Does My Dog Need a Winter Coat?

Dogs that usually benefit from a coat

• Small and toy breeds, which lose body heat quickly and sit close to cold, wet ground.
• Dogs with short or thin coats, such as Chihuahuas, Boxers and French Bulldogs.
• Lean breeds with little body fat, such as Greyhounds, Whippets and Italian Greyhounds.
• Puppies and seniors, who find it harder to regulate their body temperature.
• Dogs with health conditions. Ask your vet whether extra warmth would help.

Dogs that usually don't

Thick, double-coated northern breeds such as Siberian Huskies, Alaskan Malamutes and Samoyeds were built for snow. Their coats insulate them well, and a jacket can make them overheat. Still, watch your own dog: age, health and body condition matter as much as breed.

Wet cold is harder than dry cold

A soaked coat loses much of its warmth. The Tufts Animal Care and Condition scale, a tool animal welfare professionals use to judge weather risk, raises a dog's cold-weather risk score for toy breeds and for dogs out in rain or sleet, and lowers it for northern or heavy-coated breeds. As one veterinarian told NPR: "Under 30 degrees, factoring in the wind chill, it's not going to be safe for any dog to be outside for an extended period of time."

4 signs your dog is cold

1. Shivering or trembling
2. Lifting paws off the ground
3. Hunching, tucking the tail or slowing down
4. Pulling toward home or refusing to keep going

If you see these, head inside and warm up. If your dog seems weak, confused or very lethargic after time in the cold, call your vet.

How to Measure Your Dog for a Coat in 3 Steps

Grab a soft tape measure and a few treats, and measure while your dog stands square on all four feet.

1. Back length: from the base of the neck, where the collar sits, to the base of the tail. Many coat size charts are built on this number.
2. Chest girth: around the widest part of the ribcage, just behind the front legs. Deep-chested dogs often need to size by this number.
3. Neck: around the base of the neck, where a collar sits.

Weigh your dog too, since some size charts list weight ranges. Then compare your numbers with the size chart on each product page, because sizes vary between styles. If your dog falls between two sizes, choose the larger one.

What a Good Fit Looks Like

• You can slide two fingers under the neck opening and the chest strap.
• The coat covers the back to just before the base of the tail.
• The front legs move freely, with no rubbing in the armpits.
• Your dog can sit, lie down and relieve themselves comfortably. On male dogs, check that the belly panel sits well forward.
• Nothing dangles or drags along the ground.

Choosing the Right Coat for Your Weather

Dry, cold days: puffers and soft layers

For crisp, dry walks, warmth comes first. The Alpine Pup Puffer is a soft, durable polyester puffer in sizes XS to XXXL, and the Trailblazer Fleece is a soft, relaxed layer that moves with your dog on every walk.

Wet, cold days: waterproof shells

If your winters bring more rain and slush than snow, waterproofing matters most. The Rain-Ranger Coat is made from durable waterproof material, and the Zip-and-Go is a quilted puffer vest in waterproof polyester with an easy zip-up fit.

Dark evenings: reflective detailing

Many winter walks happen after dark. The Reflective Dog Coat combines a waterproof build with reflective detailing. For more ideas, read our 9 tips for walking your dog safely at night.

Big dogs feel the cold too

Large, short-coated dogs need warmth as well. The Trailblazer Fleece runs all the way up to size 9XL, for dogs up to about 35 kg (77 lb).

Coat Care and Safety

• Take it off indoors. Coats are for outside; inside, your dog can overheat.
• Dry it between walks. A damp coat chills rather than warms. Hang it to dry, and keep a spare for very wet weeks.
• Check for rubbing. In the first week, look at the armpits and chest for redness or flattened, matted fur.
• Protect paws too. Wipe paws after walks to remove de-icing salt. Our Fall & Winter Survival Guide has more cold-weather tips.

Warm Dog, Longer Walks

The right coat isn't just a fashion statement, though it can be that too. It's the difference between a dog who dreads the front door and one who can't wait to get out there. Measure once, choose for your weather, and enjoy every frosty walk together.

Find the perfect fit. Browse the Winter Collection for puffers, fleeces and waterproof coats, and use the three-step guide above to order the right size first.

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Sources: Tufts Animal Care and Condition (TACC) scales · NPR, How Cold Is Too Cold for Pets? (2018)

This article is for general information only and isn't a substitute for professional veterinary advice. If you're worried about your dog's health, please talk to your veterinarian.