In a fuel system for an internal combustion engine, the fuel is pumped by a high-pressure fuel pump into a fuel pressure accumulator, from which it is supplied into at least one combustion chamber via at least one injector. A value is provided for the actual pressure in the fuel pressure accumulator. A pressure regulating device using which the fuel may be extracted from the fuel pressure accumulator is precontrolled using a precontrol signal, which is ascertained taking into account a setpoint pressure in the fuel pressure accumulator. A value for a fuel quantity flowing through the pressure regulating device is taken into account when ascertaining the precontrol signal.