A multi-level, multi-branch outphasing amplifier (20-1) includes a first branch group circuit (22-1) including a first branch circuit (11) receiving a first RF input signal (S1(t)) and first control information (S11_Ctrl=VDD) and a second branch circuit (12) receiving the first input signal and second control information (S12_Ctrl). Each of the first (11) and second (12) branch circuits includes a power amplifier. The second control information enables the second branch circuit to be switched on or off while the first branch circuit (12) remains on. A second branch group circuit (22-2) includes a third branch circuit (21) receiving a second RF input signal (S2(t)) and third control information (S21_Ctrl=VDD) and a fourth branch circuit (22) receiving the second input signal (S2(t)) and fourth control information (S22_Ctrl). Each of the third and fourth branch circuits includes a power amplifier. The fourth control information enables the fourth branch circuit to be switched on or off while the third branch circuit remains on. A combiner (24) combines output signals of the power amplifiers to produce an output signal (SOUT(t)).