Some dogs’ coats have two layers – the undercoat, which repels water and keeps the skin warm and dry, and the outer layer, which is more course.
Dogs Most Likely to Need a Winter Coat
These breeds do not have an undercoat and are less protected from the cold:
Afghan Hound
Boston Terrier
Boxer
Chihuahua
Doberman Pinscher
French Bulldog
Maltese
Papillon
PitBull
Poodle
Portuguese Water Dog
Yorkshire Terrier
Dogs Most Likely Not to Need a Winter Coat
These breeds do have two-layer coats:
Australian Shepherd
Belgian Shepherd
Bernese Mountain Dog
Bichon Frise
Border Terrier
Collie
Corgi
German Shepherd
Golden Retriever
Labrador Retriever
Leonberger
Lhasa Apso
Newfoundland
Old English Sheepdog
Saint Bernard
Schnauzer
Shih Tzu
Spitz-type dogs (Akita, Alaskan Malamute, Chow Chow, Husky, Pomeranian, Shiba Inu and Samoyed) and Wests.
**Always look for signs that your dog is too cold, regardless of their breed, and do not leave your dog outside in the cold for extended periods of time**