Techniques and examples of determination of receiver (RX) beam for radio link monitoring (RLM) based on available spatial quasi-co-location (QCL) information in New Radio (NR) mobile communications are described. An apparatus receives downlink (DL) signaling from a network. The apparatus determines whether to extend an evaluation period of RLM based on a quasi-co-location (QCL) association provided in at least the DL signaling. The apparatus then executes extension of the evaluation period of the RLM, or not, based on a result of the determining.