The group was formed by Harry Wayne Casey, an record store employee and part-timer at TK Records in Miami. Following demo work Casey was encouraged to create his own group. The initial members were just Casey and Richard Finch, but Jerome Smith, Fermin Goytisolo and Robert Johnson were soon added to the Sunshine Band line-up. The first few songs, Blow Your Whistle (September 1973), Sound Your Funky Horn (February 1974), were R&B hits but had limited mainstream impact. However, George McCrae took Casey's Rock Your Baby and made it a great hit in mid-1974, selling over 5 million copies. KC then released the European hit Queen of Clubs and went on tour to Europe in 1975 off that success.
The group's first major US hit was in 1975 with Get Down Tonight, it topped the R&B chart in April and the Billboard chart in August. By their triple platinum second album in 1975, the eponymous KC And The Sunshine Band, the group was well established. That's The Way (I Like It) was a number one hit in November 1975 and the group did well at the 1976 Grammy awards. Their success lasted until the fifth album and 1979-80, their last chart topping hit was Please Don't Go in January 1980. With the declining popularity of disco the group explored other styles and changed label, joining Epic Records in 1980 after TK went bankrupt.
The group has released nine albums and a number of compilations. The group fell into stasis around 1985 with the retirement of Casey, but was revived in the early 1990s.