Because the touch temperature of a wearable computing device (“WCD”) may be an insignificant factor for user experience when the WCD is not being worn by a user, embodiments of the solution seek to modify thermal management policies based on an inferred user proximity state. Exemplary embodiments monitor one or more signals from readily available sensors in the WCD that have primary purposes other than measuring user proximity. Depending on embodiment, the sensors may be selected from a group consisting of a heart rate monitor, a pulse monitor, an O2 sensor, a bio-impedance sensor, a gyroscope, an accelerometer, a temperature sensor, a pressure sensor, a capacitive sensor, a resistive sensor and a light sensor. Using the signals generated by such sensors, relative physical proximity of the WCD to a user may be inferred and, based on the user proximity state, thermal policies either relaxed or tightened.