A deposition mask includes: a plurality of sub-masks through which deposition material passes to a base layer to form a deposition layer defining a hole therein, each of the sub-masks including: an aperture through which the deposition material passes to the base layer, a total planar area of the aperture corresponding to less than a total planar area of the deposition layer, and a masking surface at which the deposition material does not pass through the sub-mask, the masking surface including a hole-forming portion of which a total planar area thereof corresponds to a total planar area of the hole defined in the deposition layer. The hole-forming portions of the sub-masks have a same shape and planar area as each other, and within each sub-mask, the shape of the hole-forming portion is nested within a shape of the aperture.