A three-way poppet valve that can restrict or eliminate backflow without the use of an external check valve. Unlike conventional three-way poppet valves wherein both inlets can be open to the outlet at the same time during movement of the poppet, the valve according to the present invention can be configured to close both inlets prior to opening one of the inlets to the outlet. The valve features a poppet valve assembly that is operable to prevent both inlets from being open to the outlet at the same time. The valve assembly also reduces the force needed to close the valve against at least one of the inlets thereby allowing the use of a smaller actuator. A unique seal including a valve seat that is configured to conform to a valve member under sufficient pressure.