| Firm | City | State | Country | Chapter |
| A & H Balance Company | Lexington | KY | USA | Southwest Ohio |
| A & P Services Limited | Cornerbrook | NewFoundland | Canada | Canada |
| A.D. & M. - Testing and Balancing | West Seneca | NY | USA | WNY |
| A.E. Smith & Son Pty Ltd | Eagle Farm | Queensland | Australia | |
| A.E. Smith and Son Pty Ltd | Mulgrave | Victoria | Australia | |
| A.G. Coombs, Pty Ltd | Moorabbin | Victoria | Australia | |
| A.J. Monier & Company, Inc. | San Antonio | TX | USA | Texas |
| A.T.D. Test & Balancing Services | Guaynabo | PR | USA | Capital - Mar Va |
| Aaron Engineering Services | Chicago | IL | USA | Illinois |
| Abdullah Al-Hamoud Al-Shuwayer HVAC Testing Division | Dammam | Kingdom of Saudi Arabia | Saudi Arabia | Capital - Mar Va |
| Able Balance Corporation | Franktown | CO | USA | Rocky Mountain |
| Absolut Balancing Co., Inc. | South Lyon | MI | USA | Michigan |
| Acadian Air Balance, Inc. | Lafayette | LA | USA | North Louisiana |
| ACCO Engineered Systems | Glendale | CA | USA | Southern California |
| ACCO Engineered Systems-San Leandro | San Leandro | CA | USA | Northern CA/Hawaii |
| Accu-Flow Balancing Co., LLC | Warrington | PA | USA | MAEBA |
| Accurate Balancing & Commissioning | West Palm Beach | FL | USA | Florida |
| Accurate Balancing Agency, Inc. | Beaverton | OR | USA | Pacific Northwest |
| Accurate Test & Balance, LLC | Capital Heights | MD | USA | Capital - Mar Va |
| AccuTec Services, Inc. | Lee's Summit | MO | USA | Great Plains |
| Ace Lab Systems, Inc. | St. Louis | MO | USA | Eastern Missouri |
| ACP Sheet Metal Company, Inc. | Oklahoma City | OK | USA | Oklahoma |
| Advance Air Systems | Ft Worth | TX | USA | Texas |
| Advance Air Systems - Austin | Austin | TX | USA | Texas |
| Advance Mechanical Systems Inc. | Mt. Prospect | IL | USA | Illinois |
| Advanced Contracting Pty Ltd | Glenorchy | Tasmania | Australia | |
| Advanced Mechanical Services, Inc. | Silverdale | WA | USA | Pacific Northwest |
| Advanced Testing & Balancing Co., Inc. | West Haven | CT | USA | Northeast |
| Aero Testing & Balancing Sys. Inc. | Chicago | IL | USA | Illinois |
| Aerohydronics Inspecting Company | West Hills | CA | USA | Southern California |
| Air Adjustments & Balancing, Inc. | Schomberg | Ontario | Canada | Canada |
| Air Analysis of Atlanta, Inc. | Conyers | GA | USA | Mid South |
| Air Audit Inc. | Cambridge | Ontario | Canada | Canada |
| Air Balance Associates | Seattle | WA | USA | Pacific Northwest |
| Air Balance Engineering | Ecru | MS | USA | Arkansas |
| Air Balance Hawaii, Inc. | Honolulu | HI | USA | Northern CA/Hawaii |
| Air Balance of Omaha | Omaha | NE | USA | Great Plains |
| Air Balancing Engineers, Inc. | Berwick | PA | USA | MAEBA |
| Air Balancing Service Company | North Haven | CT | USA | Northeast |
| Air Balancing Specialty Inc. | Portland | OR | USA | Pacific Northwest |
| Air Balancing Technology | Kingsport | TN | USA | Tennessee |
| Air Control Balancing, Inc. | Fresno | CA | USA | Northern CA/Hawaii |
| Air Data - Macon, Georgia | Macon | GA | USA | Mid South |
| Air Data, Inc. | Conyers | GA | USA | Mid South |
| Air Distribution Products | Little Rock | AR | USA | Arkansas |
| AIR Engineering and Testing, Inc. | Dallas | TX | USA | Texas |
| Air Filtration Management, Inc - NY | Buffalo | NY | USA | WNY |
| Air Filtration Management, Inc. | Bethlehem | PA | USA | MAEBA |
| Air Flow Service Pty Ltd | Rowville | Victoria | Australia | |
| Air Fluid Management | Wilber | NE | USA | Great Plains |
|