An infrastructure equipment forming part of a mobile communications network for transmitting signals to or receiving signals from communications devices, the infrastructure equipment comprising a transmitter configured to transmit signals to one or more of the communications devices in accordance with a wireless access interface formed by the infrastructure equipment, and a receiver configured to receive signals transmitted by one or more of the communications devices in accordance with the wireless access interface, a controller configured to control the transmitter and the receiver to transmit data to one or more of the communications devices via a downlink of the wireless access interface or receive data from the one or more communications devices via an uplink of the wireless access interface, wherein the wireless access interface is provided with a plurality of different spacing of subcarriers for receiving signals representing the data on the uplink from the one or more communications devices or for transmitting signals representing the data on the downlink to the one or more communications devices, and the controller is configured in a combination with the transmitter and the receiver to identify a requirement to provide communications resources of the wireless access interface to one of the communications devices on the uplink or on the downlink, to select one of the plurality of different subcarrier spacing, the selected subcarrier spacing also determining whether the communications device should use a single subcarrier or multiple subcarriers, and to transmit an indication on the downlink of the wireless access interface of one of the plurality of different subcarrier spacing which the communications device should use to transmit or to receive the signals representing the data, the indicated subcarrier spacing also identifying whether the communications device should use a single subcarrier or multiple subcarriers. a transmitter configured to transmit signals to one or more of the communications devices in accordance with a wireless access interface formed by the infrastructure equipment, and a receiver configured to receive signals transmitted by one or more of the communications devices in accordance with the wireless access interface, a controller configured to control the transmitter and the receiver to transmit data to one or more of the communications devices via a downlink of the wireless access interface or receive data from the one or more communications devices via an uplink of the wireless access interface, wherein the wireless access interface is provided with a plurality of different spacing of subcarriers for receiving signals representing the data on the uplink from the one or more communications devices or for transmitting signals representing the data on the downlink to the one or more communications devices, and the controller is configured in a combination with the transmitter and the receiver to identify a requirement to provide communications resources of the wireless access interface to one of the communications devices on the uplink or on the downlink, to select one of the plurality of different subcarrier spacing, the selected subcarrier spacing also determining whether the communications device should use a single subcarrier or multiple subcarriers, and to transmit an indication on the downlink of the wireless access interface of one of the plurality of different subcarrier spacing which the communications device should use to transmit or to receive the signals representing the data, the indicated subcarrier spacing also identifying whether the communications device should use a single subcarrier or multiple subcarriers.