SAfm was the SABC's first radio station, and the country's first public radio station. From 1924 to 1936, the only radio service in South Africa was a privately owned station called JB, which broadcast to the cities of Johannesburg, Durban, and (later) Cape Town. An Act of Parliament in 1936 made official the conversion of JB into a public broadcaster.

In its early days as a public radio service, the station was called the "A" Programme. When the SABC started an Afrikaans-language station in 1937, the two stations came to be called the English Service and the Afrikaans Service, respectively. In 1985 the English Service was renamed Radio South Africa; it has had its current name, SAfm, since 1995. The SAfm studio is now in SABC Radio Park, in the Johannesburg suburb of Auckland Park.