A terminal apparatus able to establish a connection with a base station apparatus via a two-step random access procedure by transmitting a first signal including a random access preamble and predetermined information to the base station apparatus and receiving a second signal as a reply to the first signal from the base station apparatus, wherein
- the terminal apparatus acquires a random access-radio network temporary identifier (RA-RNTI) by adding a predetermined offset value to a value acquired on the basis of a radio resource having been used to transmit the random access preamble with the first signal, and
- the terminal apparatus executes reception processing of the second signal using the RA-RNTI,
- wherein the terminal apparatus is further able to establish a connection with the base station apparatus via a four-step random access procedure, and
- in a case where the four-step random access procedure is used, the terminal apparatus acquires a second RA-RNTI on the basis of a radio resource having been used to transmit a random access preamble from the terminal apparatus to the base station apparatus via the four-step random access procedure and executes reception processing of a random access response, which is a reply to the random access preamble, using the second RA-RNTI.