Abstract: A clamshell screw anchor is provided which is inexpensive to manufacture, installable in many types of soils including rocky and frozen soils, and is adaptable for use in various applications, such as supporting electric transmission poles. The screw anchor broadly includes a unitary body member, a core, and a helical load bearing element. The body member is stamped from a substantially flat piece of material, and presents a pair of opposed, elongated body segments depending from a line of symmetry. Each of the body segments includes a first end shaped to define a hub element having a C-shaped cross section, a second end shaped to define a lead point element, and a pair of longitudinally extending side edges. The body member is folded about the line of symmetry, and the body segments are secured together along the side edges so that the hub elements form a hub having an open, upper end, and a rectangular cross-sectional shape, and the lead point elements form a lead point having an earth-engaging tip.