CBCS-FM is a Canadian radio station. It is the CBC Radio One station in Sudbury, Ontario, broadcasting at 99.9 FM, and serves all of Northeastern Ontario through its network of relay transmitters.
The station was launched in 1978 on FM 99.9 MHz. Prior to its launch, CBC Radio programming aired on private affiliates CKSO and CKSO-FM.
The CRTC decision authorizing the launch of CBCS in fact encouraged, but did not direct, the CBC to retain an AM frequency for CBC Radio, and to reserve CBCS for its CBC Stereo network. However, the station launched in 1978 as an affiliate of the talk network after the CBC was unable to negotiate an agreement with Cambrian Broadcasting to directly acquire CKSO.
The CBC later applied for a second license for its Stereo network, which was granted in 1984. However, that station remain unlaunched throughout the 1980s, and the CBC was forced in 1991 to surrender all of its non-operating licenses. Consequently, CBC Radio 2 service was not available in the city until the launch of CBBS-FM in 2001.