We report on two-dimensional photonic crystal designs in vertical-cavity surface-emitting lasers that yield single-transverse mode operation over a wide range of wavelengths (780, 850, and 980 nm). These single-mode photonic crystal designs are consistent with predictions of a theoretical model that considers design parameters such as hole diameter, lattice constant, and etching depth. The single-mode lasers demonstrate side mode suppression of > 35 db and > 1 mW output power using the same photonic crystal pattern.