Reg or REG may refer to:
- Reginald
- Desert pavement, a vast stony plain in a desert
- Random event generator (parapsychology)
- Raptor Education Group
- Regal Entertainment Group
- Regular language
- Richard E. Grant, British actor
- .reg (also known as Registration entries), text-based human-readable files for storing portions of MS Windows registry
- Registration, such as for a motor vehicle
- Regina, Latin for Queen, typically on coins or in law
Read more about Reg: Places