Glossary

Double coat

A coat made of a soft insulating undercoat beneath longer, coarser guard hairs, found in many cold-climate and semi-longhair breeds.

Also called: double-coated, two-layer coat, dense coat

A double coat has two layers. The undercoat is dense and soft, and traps warm air next to the skin. Over it lie the longer, coarser guard hairs, which repel water and dirt and give the cat its colour and pattern. Together they insulate against cold and wet. Breeds that evolved in harsh climates, such as the Norwegian Forest Cat, Siberian and Maine Coon, often have thick double coats, and so do many domestic longhairs and semi-longhairs.

Double-coated cats usually shed the undercoat in larger amounts when the seasons change, typically in spring and sometimes in autumn. Brushing once or twice a week removes loose fur before it mats or ends up swallowed, and a daily brush helps during a heavy moult.

Resist the urge to shave a double-coated cat in summer. The coat helps regulate temperature in both directions, and the regrown hair may look different. A professional clip is sometimes needed for severe matting, and your vet or groomer can decide. See undercoat and guard hairs for the two layers.

Last reviewed November 7, 2026

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Related terms

Undercoat The soft, fine, dense layer of fur closest to a cat's skin that provides most of its insulation. Guard hairs The long, coarse outer hairs of a cat's coat that shed water and dirt and carry its colour and pattern. Ruff A collar of longer fur around a cat's neck and chest, most obvious in breeds such as the Maine Coon and Norwegian Forest Cat. Britches The long, full fur on the backs of a longhaired cat's hind legs, which forms a pair of fluffy trousers.

Related guides

How to brush a cat How to choose a brush, groom short and long coats, handle mats and shedding, and make brushing something your cat accepts or enjoys. Keeping a cat cool in hot weather How to help a cat cope with heat, the signs of overheating that need a vet at once, and which cats are at higher risk.