RTL may refer to:
Media
- RTL Group, a European TV, radio, and production company
- RTL Télé Lëtzebuerg, usually referred to simply as RTL
- RTL (German TV channel)
- RTL (French radio)
- RTL Nederland
- List of RTL Group's television stations (including part-owned channels)
- List of RTL Group's radio stations
- RTL 102.5, Italian radio station unaffiliated with RTL Group
- RTL9, Luxembourg television channel formerly owned by RTL Group
Electronics
- Prefix for some Realtek integrated circuits
- Register-transfer level or register-transfer logic, of a digital logic circuit
- Register transfer language, a type of computer language
- Hewlett-Packard Raster Transfer Language, a subset of PCL
- Resistor–transistor logic, a class of digital circuits
Others
- RTL Turboliner, a gas turbine trainset
- Right-to-left, writing direction of a script
- Re-education through labor in the prison system of China
- Réseau de transport de Longueuil, Quebec, Canada
- Runtime library, in computer software