User equipments (UEs) and methods for hybrid automatic repeat request acknowledgement (HARQ-ACK) operation in a sidelink. A user equipment configured to receive a physical sidelink control channel (PSCCH) that includes a sidelink control information (SCI) format scheduling a reception of a physical sidelink shared channel (PSSCH) that includes a transport block (TB) and to provide HARQ-ACK information for the TB decoding in a physical sidelink feedback channel (PSFCH).