A fan-out semiconductor package includes: a semiconductor chip having an active surface having connection pads disposed thereon and an inactive surface opposing the active surface; an encapsulant encapsulating at least portions of the semiconductor chip; a connection member disposed on the active surface of the semiconductor chip and including a redistribution layer electrically connected to the connection pads; a passivation layer disposed on the connection member and having openings exposing at least portions of the redistribution layer; metal members disposed in the openings of the passivation layer and connected to the exposed redistribution layer; and electrical connection structures disposed on the passivation layer and connected to the metal members, wherein the electrical connection structures have heights hierarchically differentiated from one another depending on sizes of the metal members.