A user apparatus includes, a control unit configured to apply in a specific order a plurality of processing rules for determining a channel as a transmission candidate by dropping a channel or multiplexing channels and repeat the application until detecting no channel collision in a time domain, in a case where a channel associated with a first service type and a channel associated with a second service type collide with each other at least in a time domain, and for at least one of the channel associated with the first service type and the channel associated with the second service type, a plurality of channels associated with a same service type collide with each other at least in the time domain; and a transmitting unit configured to transmit, to a base station apparatus, the channel as the transmission candidate for which no channel collision is detected in the time domain.