Apparatus and method are provided for small cell energy saving. In one novel aspect, switch-off-request is broadcasted by the small cell detecting the low-load condition. The small cells upon receiving the switch-off-request message enter the frozen state, which prevents the small cells from switching off. In another novel aspect, the small cell in the low-load condition request measurement reports from the UEs. The UEs replies with the measurement-reports message, which includes the detected neighboring IDs and the UE's traffic load. The low-load small cell includes the information derived from the measurement-reports in the switch-off-request message. In another novel aspect, the small cell broadcasts the switch-on-request message. Upon receiving switch-on-acknowledge messages from switched-off neighboring small cells, the small cell selects one or more target cells to send the cell-activation-request. The switched-off small cells, upon receiving the request to switch-on, uses a cost function to determine whether to switch on.