Systems and methods related to switched carrier Sounding Reference Signal (SRS) transmission in unlicensed spectrum are disclosed. In some embodiments, a method of operation of a User Equipment device (UE) in a wireless system comprises performing uplink Listen-Before-Talk (LBT) on one or more candidate carriers for switched carrier SRS transmission and performing a switched carrier SRS transmission on at least one candidate carrier of the one or more candidate carriers that is determined to be available as a result of performing the uplink LBT on the one or more candidate carriers. In some embodiments, the one or more candidate carriers are carriers other than carriers configured for the UE and on which the UE is scheduled to transmit.