Arts and entertainment •
Radio Corporation of Singapore •
Radcliffe Choral Society, a choral ensemble at Harvard University, US •
RCS MediaGroup (formerly Rizzoli-Corriere della Sera), an Italian publishing group •
Royal Conservatoire of Scotland •
Ryan Cayabyab Singers, a Philippine band
Education •
Rawmarsh Community School, South Yorkshire, England •
Richmond Christian School, British Columbia, Canada •
Rajshahi Collegiate School, Bangladesh •
Riverdale Country School, Bronx, New York, US •
Rogersville City Schools, a school district, Tennessee, US •
Rosehill Christian School, Texas, US •
Royal College of Science, a former higher education institution, London, England •
Royal College of Surgeons, an ancient college in England
Military •
Regional Command South (RC-S), part of NATO's Resolute Support Mission within Afghanistan •
Royal Corps of Signals, of the British Army
Sport •
RC Strasbourg Alsace, a French football club •
Representation of Czechs and Slovaks, a football team
Other organisations •
Red Crescent Society •
Red Cross Society •
Romania Cable Systems •
RCS Motor Club, who maintain an antique fire engine for the Royal College of Science •
Radio Computing Services, an American software company ==Places==