A fuel system for an internal combustion engine includes at least one first fuel pump and a pressure region into which the fuel pump pumps and which communicates with an elastic volume reservoir. The elastic volume reservoir has a characteristic pressure/volume curve, which is defined by at least two points. It is proposed that a first point is defined by a first volume at a first pressure that is somewhat greater than a vapor pressure of the fuel at ambient temperature, and that a second point is defined by a second volume and a second pressure in the pressure region that corresponds to a maximum pressure; the difference between the first and second volumes corresponds at least approximately and at least to a value by which the volume of the fuel in the pressure region decreases upon cooling down from a maximum temperature to ambient temperature.