Embodiment techniques map parity bits to sub-channels based on their row weights. In one example, an embodiment technique includes allocating, from a set of sub-channels, one or more sub-channels for one or more parity bits based on row weights for sub-channels in a subset of sub-channels within the set of sub-channels, mapping information bits to remaining sub-channels in the set of sub-channels based on a reliability of the remaining sub-channels without mapping any of the information bits to the one or more sub-channels allocated for the one or more parity bits, polar encoding the information bits and the one or more parity bits based on at least the mapping of the information bits to the remaining sub-channels to obtain encoded bits, and transmitting the encoded bits to another device.