Techniques are provided for retransmission of Physical Uplink Shared Channel (PUCCH) for Ultra Reliable Low Latency Communications (URLLC). A User Equipment (UE) transmits at least one code block of a control channel, the at least one code block including Channel State Information (CSI), wherein each code block is polar encoded by assigning bit indices of the code block to bit channels in a particular order of reliabilities of the bit channels. The UE detects a trigger, and in response, retransmits at least a portion of each code block including retransmitted CSI, wherein the portion is polar encoded by assigning bit indices of the retransmitted CSI to the bit channels in the reverse order of reliabilities of the bit channels as compared to the polar encoding of the CSI.