KYSX is a commercial radio station licensed to Billings, Montana, USA, broadcasting on 105.1 FM. It was owned by BMG Billings, LLC, but is now owned by Radio Billings, LLC. The station has obtained a construction permit from the U.S. Federal Communications Commission (FCC) for a frequency change to 104.5 MHz and a power increase to 100,000 watts.Prior to December 2, 2008, it was an adult hits station known as "Bill FM".