The coat, from which the breed derives its name is another important characteristic. The hair is long, soft, supple, dense and dry with the texture of cotton. The main colour is white, with slight shadings of grey or red-roan permitted on the ears.

Many puppies are born with black or brown markings on their faces and bodies. In most cases, these markings fade to a grey or light-brown colour by about the age of two years. Occasionally, black or brown patches remain quite dark. For the show ring, the coat is left unscissored with the exception of a little trimming around the paws and the pads of the feet. Adult dogs require a deep brushing once or twice weekly to maintain a long coat.

Many pet owners prefer to have their companions trimmed in a puppy cut that tends to accentuate their playful nature. The Coton does not have dander in its coat, so it may be a good choice for people with allergies. They do not shed like other dogs, but loose hair like humans, especially when being brushed