A pressure regulating valve for an inkjet printhead. The valve includes: a valve inlet connect to a valve outlet; via a flow path; a first orifice positioned in the flow path having a sealable first seat; a movable first valve member configured for sealing engagement with the first seat; a second orifice positioned in the flow path; a movable second valve member configured for regulating a fluid flow rate through the second orifice; a regulator chamber having the valve outlet and comprising a diaphragm operatively connected to the second valve member, such that movement of the diaphragm moves the second valve member relative to the second orifice; and a biasing mechanism for resiliently biasing the diaphragm away from the second orifice.