The described technology is generally directed towards radio unit cascading in radio access networks. Radio units (RUs) can be configured with processors adapted to support daisy chaining of multiple RUs, so that the multiple RUs can connect to one hardware interface at a distributed unit (DU). An RU processor for a given RU can be configured to receive downlink data, including downlink data for the given RU as well as downlink data for other downstream RUs. The RU processor can extract the downlink data for the given RU and forward the downlink data for other downstream RUs via a southbound interface. The RU processor can also be configured to receive uplink data from the other RUs, multiplex the received uplink data from the other RUs with uplink data from the given RU, and send the resulting multiplexed data towards the DU via a northbound interface.