In a radial compressor stage for a radial compressor having a rotor side, the radial compressor stage includes a stator; and an impeller configured to rotate relative to the stator. The impeller has multiple impeller blades on the rotor side. Each of the multiple impeller blades has: a flow inlet edge, a flow outlet edge, a suction side extending between the flow inlet edge and the flow outlet edge, a pressure side, and an outer surface facing the stator. At least one groove is arranged in the outer surface of at least one of the multiple impeller blades, the at least one groove being bounded by a longitudinal web both on the suction side and on the pressure side. Each of the longitudinal webs forms a sealing tip of the respective impeller blade towards the stator.