A radio communication terminal, a radio communication base station device, and radio communication method enabling lightening the paging load in a mobile communication system including macro cells and femto cells. A reception level measuring section (144) of a UE (104) measures the reception level of a femto cell. If a judging section (146) judges that the measured reception level is over a level which is the sum of a threshold and an offset value, the judging section (146) requests an MME (101) to change a multi TA registration to a single TA registration and carries out a change to one tracking area registration.