A compensation coil placed at least partially underneath a magnetic field sensor package in an electronic system provides attenuation of electromagnetic interference (EMI). In an embodiment, the compensation coil attenuates EMI in a frequency band which overlaps with an operating frequency band of the magnetic field sensor. This allows the magnetic field sensor to make accurate magnetic field measurements in the presence of system level alternating current (AC) EMI. In an embodiment, a system comprises: a magnetic field sensor; a compensation coil placed at least partially underneath the magnetic field sensor; and a reverse current generator coupled to the compensation coil and to a power supply that is coupled to an electromagnetic interference (EMI) source, the reverse current generator operable to generate a reverse current in the compensation coil to generate a counter magnetic field for compensating the EMI.