A port (1) for a catheter comprises: a housing (10) having a base plate (12)； a cavity (140) arranged in the housing (10) for receiving a fluid； a membrane (13) attached to the housing (10) and arranged on an opening (102) of the housing (10) for sealing the opening (102) such that the cavity (140) is enclosed in the housing (10) in a fluid-tight manner； and a connector (15) for connecting a catheter (2) to the housing (10) to provide a fluid connection between the cavity (140) and the catheter (2). The port (1) has an outer shape defined by the housing (10) and the membrane (13) attached to the housing (10). In addition at least one adapter piece (3, 4) is provided, the at least one adapter piece (3, 4) in a preassembly state being separate from the housing (10) and being attachable to the housing (10) to alter the outer shape of the port (1), wherein the port (1) is operational with or without the at least one adapter piece (3, 4) attached to the housing (10). In this way a port is provided which in a uniform manner may be used with different patients.
