Techniques are provided for Wake up signal monitoring in a radio resource control connected (RRC) mode. An example method can include a user equipment (UE) determining capability information associated with wake-up signal (WUS) monitoring, the capability information to include an indication that the UE supports WUS monitoring in a radio resource control (RRC) connected mode. The UE can transmit, to a base station, an indication of the capability. The UE can perform, while in a sleep state in which transmitting and receiving by a main radio is suspended, WUS monitoring to detect a trigger. The UE can transition from the sleep state to the awake state based on the trigger. The UE can monitor for a downlink (DL) transmission in the awake state.