A windshield washer fluid heater for an automotive vehicle has an elongated housing with two open ends and in which the housing defines a housing chamber. A tubular subhousing divides the housing chamber into an outer housing chamber and an inner housing chamber. A core is disposed in the inner housing chamber and this core forms an annular chamber between the core and the subhousing. A pair of end caps is attached to the ends of the housing and these end caps sealingly engage the housing and the subchamber to fluidly separate the outer housing chamber from the annular chamber. The housing includes a washer fluid passageway which fluidly connects a washer fluid port on the end cap with the annular chamber as well as a coolant fluid passageway which fluidly connects a coolant port on each end cap with the housing chamber.