BLS
- BL (disambiguation)
- BL S-series engine
- BLS AG
- BLS digital signature
- BLSS (disambiguation)
- Bachelor of Liberal Studies
- Bachelor of Library Science
- Bacterial leaf scorch
- Balaesang language
- Bare lymphocyte syndrome
- Basic life support
- Basketball League of Serbia
- Bears Lagoon Serpentine Football Club
- BellSouth
- Black Label Society
- Blind loop syndrome
- Boston Latin School
- Brighton le Sands (disambiguation)
- Brillouin light scattering
- Brooklyn Law School
- Bucerius Law School
- Buckeye Leadership Society
- Bureau of Labor Statistics
- CBLS
- Cadillac BLS
- Fastest animals
- History of Brighton-Le-Sands, New South Wales
- KBLS
- WBLS