A thermal management system for a vehicle is disclosed, wherein the vehicle comprises an occupant compartment and a propulsion system configured to provide motive power to the vehicle. The system comprises a propulsion coolant circuit configured to cool at least a portion of the propulsion system, a heating circuit configured to heat the occupant compartment, and a heat pump circuit comprising a first evaporator in the propulsion coolant circuit and a condenser in the heating circuit. The propulsion coolant circuit comprises a connecting conduit connecting the propulsion coolant circuit to the heating circuit at a position upstream of the condenser, and a first valve configured to control flow of coolant through the connecting conduit. The present disclosure further relates to a powertrain for a vehicle, as well as a vehicle.