Curable phase change inks contain an ink vehicle, a pigment and a dispersant. A base ink set is of colored phase change inks that utilize the same dispersant, and also desirably contain the same amount of the dispersant. This allows the different color curable phase change inks to be mixed together while avoiding incompatibilities between each other, resulting in custom colors and a reliable expanded color gamut for the base ink set. Also, a method of forming images with the custom color curable phase change inks is disclosed.