Harlequin is a form of Merle and as such behaves similarly. It turns the base coat to become white or off-white, with random shaped dark grey or black spots along the white in natural patterns. Usually more common are smaller spots, with the occassional larger spot.

• Spots cannot be large enough to cover the entire design with black and very little white. It should be obvious that the design is white with black spots.
• Be careful to not have the spots look small enough to be confused with flecking.

Though rare, Double Harlequin can happen when two Harlequin Warhounds are bred together. These pups are mostly white with very few dark spots, usually only in one place on the coat, with the rest a pure white colour, similar to albino. These pups have a high chance of deafness, blindness, or death at birth.