Brown horses have a dark brown coat, black lower legs, mane and tail and a lighter brown muzzle.

The colour of a brown horse can vary from dark brown to almost black and during the winter a brown horse is often darker than during the summer.  They can be distinguished from black or dark bay as their muzzle, the area around the eyes, flanks and around the stifle area are a lighter shade of brown.

Brown horses are the result of the black base colour combined with gene similar, but separate, to the agouti gene that controls the expression of black.