<p>This paper proposes an optimized belief propagation decoder for polar codes in Fifth-Generation (5G) New-Radio (NR), leveraging a processing element based on one’s complement. By utilizing one’s complement, the design reduces the number of adders, thereby shortening the critical path within the processing element. This optimization not only decreases critical path delay but also minimizes the hardware resource requirements, enhancing overall hardware efficiency. The proposed belief propagation decoder synthesized using Xilinx Vivado, with one’s complement processing element achieves a 15% reduction in area compared to the conventional decoder. It also reduces the critical path of the processing element by 2T_adders compared to the SMS-BP decoder.</p>