A method (200) and apparatus (100) for calibrating a global positioning system oscillator is disclosed. The apparatus may include a global positioning system receiver (120), a temperature compensated oscillator (130) coupled to the global positioning system receiver, a controller (140) coupled to the global positioning system receiver, and an offset module (150) coupled to the controller. The controller can control the operations of the apparatus. The offset module can send a calibration signal to the global positioning system receiver using values corresponding to an oscillator frequency rate of change vs. time.