RGS
RGS can be a three-letter acronym for:
- Regulators of G-protein Signaling (see GTPase)
- Royal Geographical Society
- Royal Geological Society
- Any one of the Royal Grammar Schools in the United Kingdom:
- Royal Grammar School, Guildford
- Clitheroe Royal Grammar School
- Colchester Royal Grammar School
- Lancaster Royal Grammar School
- Royal Grammar School, High Wycombe
- Royal Grammar School, Newcastle
- RGS Worcester and The Alice Ottley School previously "Royal Grammar School Worcester" prior to 2007
- Reigate Grammar School
- Raffles Girls' School (Secondary)
- Rio Grande Southern Railroad reporting mark - RGS
- Redland Green School, Bristol
The three-letter acronym is part of:
- The automobile RGS Atalanta (See Atalanta (1937 automobile))