BTA may refer to:

• Butyric acid
• Baltimore Transit Alliance
• Basic Trading Area, a geographical area defined by the U.S. Federal Communications Commission
• Becoming the Archetype, a Christian metal band
• Benzotriazole
• Bicycle Transportation Alliance
• Bilateral trade agreement
• Bilateral Terran Alliance, a fictional human alliance in the 1985 film Enemy Mine
• Biological Terrain Assessment
• Black Theatre Alliance, a federation of theater companies in New York City
• BlueTooth Address
• Bolshoi Teleskop Azimutalnyi, a 6 m telescope located in Russia
• Botswana Telecommunications Authority
• British Tourist Authority
• British Triathlon Association, the former name of the British Triathlon Federation
• BTA Bank, of Kazakhstan, formerly Bank TuranAlem
• Bulgarian News Agency
• Business Technology Association
• Business Transformation Agency
• Board of Tax Appeals
• Airport code for Blair Municipal Airport