The modular relay has a base (1) on which a relay system (2, 3, 4) is constructed, as well as a printed circuit board (6) which stands upright on the base. Contact elements (41c, 42c, 43) of the relay are directly connected to flat connectors in the base, via conductor elements. Further conductor elements in the base likewise form flat connectors as connections for a modular circuit which is arranged on the printed circuit board. All conductor elements of the base additionally form solder connecting pins (51b to 56b), which are integrally formed, which all emerge in a row on one side wall of the base, and which are soldered to the printed circuit board in the lower edge region of said printed circuit board. This results in a compact modular structure for a relay having a maximum number of connecting elements, the allocation of these connecting elements being variable for different modular circuits.