Reg may refer to:
- Random event generator
- The stock market abbreviation for the motion picture exhibition company Regal Entertainment Group
- A vast stony plain in a desert
Reg may also be a short form for a variety of names and terms.
- The forename Reginald
- Regina (Latin for Queen), typically on coins or in law
- Registration
- Regulation
- Regular
- Reggio Calabria Airport
Reg may also refer to one of two districts in Afghanistan.
- Reg District (Helmand)
- Reg District (Kandahar)
