Apparatus for determining downhole fluid temperatures are described. An example apparatus for measuring a temperature of a downhole fluid includes a sensing element for measuring a physical or chemical property of the downhole fluid, and a plurality of electrical connections to enable the sensing element to measure the chemical or physical property and provide an output signal representative of the chemical or physical property, wherein at least one of the electrical connections is configured to function as a thermocouple to sense a temperature of the downhole fluid.