Integrated circuit devices including standard cells are provided. The standard cells may include a first vertical field effect transistor (VFET) including a first channel region and having a first conductivity type and a second VFET including a second channel region and having a second conductivity type that is different from the first conductivity type. Each of the first channel region and the second channel region may extend longitudinally in a first horizontal direction, and the first channel region may be spaced apart from the second channel region in a second horizontal direction that is perpendicular to the first horizontal direction.