An apparatus and system for deferring hybrid automatic repeat request (HARQ) feedback for semi-persistent scheduling (SPS) physical downlink shared channel (PDSCH) transmissions in a time-domain duplexing (TDD) system are described. After an SPS PDSCH configuration indicating that deferral of the SPS HARQ feedback is enabled is received, a user equipment (UE) determines whether a PUCCH associated with a particular SPS PDSCH transmission is able to be transmitted on valid uplink (UL) symbols. The PUCCH carries a SPS HARQ-ACK bits to acknowledge the particular SPS PDSCH transmission. If the PUCCH is unable to be transmitted using the timing of the SPS PDSCH configuration, the transmission is deferred until the next valid occasion on which the PUCCH is able to be transmitted.