A single quantum well laser with a 2‐mm‐wide aperture has exhibited low threshold current density and nearly 100% packing fraction. The lateral structure relies on epitaxial growth on a corrugated substrate to frustrate radiative lateral processes and it thus eliminates the need for isolation at least for incoherent operation. Threshold current densities are comparable to those for low‐power devices, and slope efficiencies remain undiminished to our current limit where 10.7 W per facet is attained. The aperture size is limited only by our fixturing arrangement.