Modem System Selection Optimization in WLAN-Only Mode

Various embodiments include methods performed by a processor of a computing device for managing Radio Access Technology (RAT) capability during a Wireless Local Area Network (WLAN)-only mode. Various embodiments may include determining whether the computing device is in a WLAN-only mode, and removing circuit-switched RATs from the RAT capability of the computing device in response to determining that the computing device is in the WLAN-only mode. This determination may be made during system bootup of the computing device, upon detecting the change in the WLAN settings and/or based on a notification message from a multimedia subsystem indicating that the computing device is in the WLAN-only mode. Some embodiments may further include transmitting a service request with only packet-switched (PS) RATs included in a RAT priority list to a Non-Access Stratum (NAS) layer of the computing device, in which the PS RATs include Long Term Evolution (LTE) and New Radio (NR).