We propose a low-power redundant flip-flop to be operated with high reliability over 1 GHz clock frequency based on the low-power (ACFF) and the highly-reliable (BCDMR) flip-flops. Its power dissipation is almost equivalent to the transmission-gate FF at 10% data activity while paying 3 × area penalty. Experiments by α-particle and neutron irradiation reveal its highly-reliable operations with no error at 1.2 V and 1 GHz. We measured five different process corner chips by α irradiation. Soft error rates are almost equivalent in these corner chips.