A method, apparatus and computer program product resolve the problem of unbalanced loads in an EVSE cluster of multiple EVSE charging stations. A signal is provided to the EVSEs identifying which phase of the three-phase power source has the highest current. When one of the EVSEs in the cluster determines whether it is connected to an EV's on board charging device, determines whether it is already charging the connected EV, and determines whether the EVSE is using the phase that has the highest current, then the EVSE may transmit a cluster load balancing control signal as a control pilot signal to the EV's onboard charging device to adjust the charging rate of the current that the EV is consuming from the EVSE.