A method for operating a communications device in a wireless communications network, the method comprising: transmitting a random access message (420, 564, 566) on a wireless access interface, the wireless access interface being divided in time into timeslots, each time slot including a plurality of Orthogonal Frequency Division Multiplexed, OFDM, symbols having in the frequency domain a plurality of sub-carriers, and provides a physical random access channel, PRACH, on an uplink carrier in one or more of the time slots, the random access message (420, 564, 566) comprising a selected random access preamble, the selected random access preamble being transmitted using time and frequency communications resources corresponding to an occasion of the PRACH, receiving a resource allocation message (424, 568) comprising an indication of downlink communications resources allocated for the transmission of a random access response message combined with a radio network terminal identifier which identifies the communications device which transmitted the random access message, determining that the resource allocation message (424, 568) identifies the communications device, and in response to determining that the resource allocation message identifies the communications device, receiving and decoding the signals transmitted using the allocated downlink communications resources, the determining that the resource allocation message (424, 568) identifies the communications device comprising calculating the radio network terminal identifier which is used in the resource allocation message to identify the communications device using an offset, and confirming that the calculated radio network terminal identifier corresponds with the radio network terminal identifier present in the resources allocation message, wherein the calculating the radio network terminal identifier comprises calculating the radio network terminal identifier based on one or more of an index of a first of a plurality of OFDM symbols of a time slot of the PRACH occasion from which the transmission of the selected random access preamble begins, the selected random access preamble occupying a plurality of the OFDM symbols, an index of a time slot number in which the selected random access preamble was transmitted in a PRACH occasion in a system frame, a subcarrier spacing, an index of the PRACH occasion in the frequency domain, and an uplink carrier used. transmitting a random access message (420, 564, 566) on a wireless access interface, the wireless access interface being divided in time into timeslots, each time slot including a plurality of Orthogonal Frequency Division Multiplexed, OFDM, symbols having in the frequency domain a plurality of sub-carriers, and provides a physical random access channel, PRACH, on an uplink carrier in one or more of the time slots, the random access message (420, 564, 566) comprising a selected random access preamble, the selected random access preamble being transmitted using time and frequency communications resources corresponding to an occasion of the PRACH, receiving a resource allocation message (424, 568) comprising an indication of downlink communications resources allocated for the transmission of a random access response message combined with a radio network terminal identifier which identifies the communications device which transmitted the random access message, determining that the resource allocation message (424, 568) identifies the communications device, and in response to determining that the resource allocation message identifies the communications device, receiving and decoding the signals transmitted using the allocated downlink communications resources, the determining that the resource allocation message (424, 568) identifies the communications device comprising calculating the radio network terminal identifier which is used in the resource allocation message to identify the communications device using an offset, and confirming that the calculated radio network terminal identifier corresponds with the radio network terminal identifier present in the resources allocation message, wherein the calculating the radio network terminal identifier comprises calculating the radio network terminal identifier based on one or more of an index of a first of a plurality of OFDM symbols of a time slot of the PRACH occasion from which the transmission of the selected random access preamble begins, the selected random access preamble occupying a plurality of the OFDM symbols, an index of a time slot number in which the selected random access preamble was transmitted in a PRACH occasion in a system frame, a subcarrier spacing, an index of the PRACH occasion in the frequency domain, and an uplink carrier used. an index of a first of a plurality of OFDM symbols of a time slot of the PRACH occasion from which the transmission of the selected random access preamble begins, the selected random access preamble occupying a plurality of the OFDM symbols, an index of a time slot number in which the selected random access preamble was transmitted in a PRACH occasion in a system frame, a subcarrier spacing, an index of the PRACH occasion in the frequency domain, and an uplink carrier used.