| A2C | Association des agences de communication créative | |
| AA | Alumni Association | |
| AA | American Association | |
| AAA | Afghan Aid Association | |
| AAA | Arkansas Activities Association | |
| AAA | Australian Automobile Association | |
| AAAA | American Association of Advertising Agencies | |
| AAAA | Alamo Area Aquatic Association | |
| AAAA | Albuquerque Aerostat Ascension Association | |
| AAAA | Alexandria Area Arts Association | |
| AAAA | American Association for Affirmative Action | |
| AAAA | American Association of Aardvark Aficionados | |
| AAAA | African American Alumni Association | |
| AAAA | Association of Accredited Advertising Agents | |
| AAAA | Asian Amateur Athletics Association | |
| AAAA | Antique Advertising Association of America | |
| AAAA | Alps Adria Acoustics Association | |
| AAAA | Australian Automotive Aftermarket Association | |
| AAAA | American Association for the Advancement of Atheism | |
| AAAA | Anguilla Amateur Athletic Association | |
| AAAA | American Association Against Acronyms | |
| AAAA | Association Against Acronym Abuse | |
| AAAA | Atlanta Area Aquarium Association | |
| AAAAA | American Association Against Alliteration Abuse | |
| AAAAA | Anderson African American Alumni Association | |
