ACA

ACA may refer to:

Arts and entertainment

Advisory Committee for Aeronautics
Aero Club of America, US aviation group, now the National Aeronautic Association
Agile Combat Aircraft, forerunner to the British Aerospace EAP technology demonstrator aircraft
Air Canada, by ICAO airline designator
Arctic Control Area, a Canadian airspace region
Astronautics Corporation of America
Atlantic Coast Airlines, later Independence Air
Austrian Cockpit Association, professional pilot organization
IATA airport code for Acapulco International Airport in State of Guerrero, Mexico

Affordable Care Act, shorthand for the Patient Protection and Affordable Care Act, commonly called "Obamacare"
Allied Commission for Austria
Anti-Corruption Agency, a Malaysian government agency
Australian Coal Association
Australian Communications Authority

Historical

Army Comrades Association, or "Blueshirts", a political organization in 1930s Ireland
Armed Peasant Association (Spanish: Asociación Campesina Armada), also known as Armed Campesino Group, a Marxist–Leninist Paraguayan rebel group

Academic Cooperation Association, international body to promote cooperation in higher education, based in Brussels
Adult Children of Alcoholics, counseling and support group
African Cashew Alliance, international organization for promoting Africa's cashew industry
American Cadet Alliance, former non-government group for military cadet activities
American Chess Association, chess organization founded in 1857 and dissolved a few years later
American Citizens Abroad, non-profit group advocating for American expatriates
American Cryptogram Association, group for cryptographic puzzles
American Crystallographic Association, scientific society
Amputee Coalition of America, advocacy and support group
Analytica Chimica Acta, scientific journal
Anti-Communist Action, a far-right organization
- NSC-131, a neo-Nazi group
Anglican Church in America, traditionalist Anglican church body
Army Comrades Association ("Blueshirts"), Irish militant right-wing group in 1932-1933
Association of Canadian Archivists, professional group for Canadian historical archivists
Atheist Community of Austin, Texas non-profit group which produces The Atheist Experience TV program
Automóvil Club Argentino, Argentina's largest automobile association
Automobile Club of America

ACA International, formerly the American Collectors Association
American Callers Association, association of square dance callers
American Camp Association, professional and trade association for summer (and similar) camp owners and workers
American Chiropractic Association, professional association
Australian Counselling Association, professional association
American Counseling Association, professional association
American Correctional Association, professional and trade association for prisons and prison officials and employees
Australasian Corrosion Association, Australia and New Zealand trade association
American College of Apothecaries, professional and trade association for independent community pharmacists

Academic Cooperation Association, international group promoting cooperation in higher education, based in Brussels

Antioch–Pittsburg (Amtrak station), by station code, in Antioch-Pittsburg, California

aca, the ISO 639 code for the Achawa language of Colombia
ACA Neo Geo, a series of Neo Geo re-releases made by Hamster Corporation and SNK, derived from Arcade Archives.
Arabic chat alphabet