RSL

RSL may refer to:

Military

 * Reserve static line, in skydiving
 * Returned and Services League of Australia, current name (since 1990) of a defence forces veterans organisation
 * Returned Sailors' and Soldiers' Imperial League of Australia (1916–1940)
 * Returned Sailors' Soldiers' and Airmen's Imperial League of Australia (1940–1965)
 * Returned Services League of Australia (1965–1990)

Sports

 * Real Salt Lake, a US soccer club
 * Royal Standard de Liège, a Belgian association football club
 * Reserve static line in skydiving
 * Rugby Super League (United States), a rugby union organization
 * Russian Superleague, a now defunct hockey league in Russia
 * Roshn Saudi League, in football, sponsors' name for the Saudi Pro League

Technology

 * RAISE Specification Language, a formal approach to software development
 * RenderMan Shading Language, a language from the RenderMan Interface Specification used for writing shaders
 * Restricted Service Licence, British limited time low power radio or television broadcasting
 * Received Signal Level, signal strength of data transmitted via radio waves

Other uses

 * Radcliffe Science Library, Oxford University
 * Raid: Shadow Legends, 2018 mobile game by Plarium Games
 * Recurrent slope lineae, surface features on Mars
 * Registered Social Landlord, a British independent public housing organization
 * Relative sea level, the distance from the ocean floor to its surface
 * Rennellese Sign Language, an extinct form of home sign documented from Rennell Island in 1974
 * Revolutionary Socialist League (disambiguation), the name of several political groups
 * Royal Society of Literature, the senior literary organisation in Britain
 * Russian Sign Language, a sign language used by the deaf community in Russia
 * Russian State Library, the national library of Russia