BAS
- BAS hybrid
- Bachelor of Applied Science
- Bachelor of Arts and Science
- Bank of America Securities
- Bas (disambiguation)
- Basaa language
- Bass (disambiguation)
- Battalion Aid Station
- Bay St. Louis station
- Behavioural Activation System
- Bere Alston railway station
- Bergen School of Architecture
- Biblical Archaeology Society
- Book of Alternative Services
- Brake assist system
- British Antarctic Survey
- British Art Show
- Broadcast auxiliary service
- Brussels American School
- Building automation
- Bulgarian Academy of Sciences
- Business Activity Statement
- South Tyrolean Liberation Committee
- United States Military Pay