Systems and methods are disclosed herein relating to rate-compatible polar codes and the use thereof in a wireless communications system. In some embodiments, a transmit node operable for use in a wireless communications system comprises a rate-compatible polar encoder operable to encode information bits to provide coded bits utilizing parallel concatenated polar codes. The transmit node further comprises a transmitter operable to transmit the plurality of coded bits. In this manner, the transmit node may, in some embodiments, use polar codes having different coding rates to adapt to time-varying channel conditions.