Examples pertaining to bit selection for polar coding incremental-redundancy hybrid automatic repeat request (IR-HARQ) are described. An apparatus (e.g., UE) generates a re-transmission polar code block (CB) in a polar incremental redundancy HARQ (IR-HARQ) procedure. The apparatus then transmits the re-transmission polar CB as a re-transmission of an initial transmission of an initial polar code carrying a plurality of information bits. In generating the re-transmission polar CB, the apparatus selects one or more re-transmission information bits from the plurality of information bits.