Methods and devices for a UE to multiplex uplink control information (UCI). The UE establishes a connection with a base station. The UE determines whether to multiplex first UCI by first identifying whether intra-priority timing overlap exists between the timing resources of the first UCI and a PUSCH with the same priority. Subsequently, the UE identifies whether inter-priority timing overlap exists between the timing resources of the first UCI and a second PUCCH with a different priority from the first PUCCH. Finally, the UE identifies whether the timing resources of the first UCI overlap with a second PUSCH with a different priority than the first PUCCH. The UE multiplexes the first UCI based on the determination whether to multiplex the first UCI, and transmits the multiplexed first UCI to the base station.