The abbreviation BAC can refer to:

• BACEngine data search tool
• Bacterial artificial chromosome
• Band-anticrossing
• the NYSE ticker symbol for Bank of America, N.A.
• Battersea Arts Centre
• Belmont Abbey College
• The Big Apple Chorus
• Blood alcohol content/blood alcohol concentration
• Boeing Airplane Company, now known as Boeing Commercial Airplanes
• Bohica Associates Corporation, now known as Bohica Associates
• The Boston Architectural Center
• The British Aircraft Corporation
• Boeing Airplane Company, now known as Boeing Commercial Airplanes
• Building Automation and Control; see Intelligent building, BACnet, and LonWorks.