A CMOS wideband voltage-mode fully differential all-pass filter (APF) is discussed. The APF circuit consists of three transistors, two inductors, two capacitors, and four resistors. The proposed APF employs the generic two-transistor common-source amplifier structure. Design procedures along with parasitic analysis are presented for wideband applications. The proposed APF is designed and fabricated in a 65-nm CMOS process. The operation of the proposed APF is validated by experimental and post-layout simulation results. The filter experimentally demonstrates a group delay (GD) of 59 ps at 26 GHz and it has less than 10% delay variation across a wide bandwidth of 24-29 GHz. The implemented design occupies an area of 186x485 μm2 and consumes 5.1 mA from 1 V supply voltage. The noise and linearity performances of the proposed APF are validated by post-layout simulation results. The filter has a noise figure of 8.6-8.9 dB across 24-29 GHz and it achieves an input-referred IP3 of -1.14 dBm.