Technology described herein provides carrier-monitoring (CM) signaling approaches that can be used by networks and/or mobile devices. An evolved Node B (eNB) can send an IncMon-support message indicating whether a network supports the increased-number-of-frequencies-to-monitor (IncMon) feature. A UE can apply a default CM configuration if the UE does not receive an IncMon-support message from the eNB. The eNB can use dedicated signaling or broadcast signaling to inform a UE of a default CM configuration or one or more adopted CM configurations that are used in the network. The eNB can also send a list of carriers that are to be monitored to the UE. The UE can also send UE-capability information to the eNB, such as a default CM configuration, an adopted CM configuration, or configurable configurations in different radio access technologies (RATs) supported by the UE.