A mother substrate for a color conversion substrate includes: a substrate including a display area and a tag area, where the tag area is disposed around the display area and includes a plurality of sub-tag areas; a first ink layer disposed in some of the sub-tag areas and having a first color; and a second ink layer disposed in some of the sub-tag areas and having a second color different from the first color. A volume of the first ink layer in each of the some of the sub-tag areas is different from each other, or a volume of the second ink layer in each of the some of the sub-tag areas is different from each other.