CHSU-FM is a Canadian radio station, broadcasting at 99.9 FM in Kelowna, British Columbia, Canada.

CHSU traces its origins to 1995, when the Canadian Radio-television and Telecommunications Commission (CRTC) granted Four Seasons Radio Ltd. a new FM licence for the Kelowna market offering country music.

One year later, in 1997, 99.9 Sun FM replaced "The Bullet" by offering a hot adult contemporary format.

In October 2007, Astral Media acquired Standard Broadcasting's terrestrial radio and television assets, including CHSU.

On October 3, 2019, CHSU dropped its long-time "Sun" branding and relaunched as 99.9 Virgin Radio.