A network based indoor positioning and geofencing system and method is described. Beacons are disposed within a physical premises and each beacon transmits a signal containing identifying information. A networked indoor positioning module receives measured reference points that include a measured beacon identifier and a measured signal strength. The networked indoor positioning module uses the measured reference points to generate calculated signal strength values for at least one detected beacon. At least one geofence is associated with the physical premises and the geofence includes some of the calculated signal strength values. A wireless device receives a beacon identifier and a beacon signal strength, when the wireless device is in or near a geofence associated the physical premises. The networked indoor positioning module determines that the wireless device is within at least one geofence by comparing the received beacon identifier and the received beacon signal strength with the calculated signal strength values corresponding to the detected beacon.