| 1 | ACW | RAF Air Cadet Schools | Callsign: Air Cadet, | GB | AVCODES |
| 2 | ACW | Servicios Aereos Across, S.A. de C.V. | Callsign: Seracro, ICAO callsign changed to Acro Jets. | MEX | AVCODES |
| 3 | ACW | Servicios Aereos Across, S.A. de C.V. | Callsign: Acro Jets, ICAO callsign changed from Seracro. | MEX | AVCODES |
| 4 | ACW | Royal Air Force | | | ICAO1 |
| 5 | ACWC | A C T CO | | | SCAC3 |
| 6 | ACWF | ACW FREIGHT SERVICES DIV WILLIAM L | | | SCAC3 |
| 7 | ACWG | AIR CARGO CORPORATION | | | SCAC3 |
| 8 | ACWH | A C T TRUCKING & WAREHOUSE INC | | | SCAC3 |
| 9 | ACWH | A C LEASING COMPANY | | | SCAC4 |
| 10 | ACWI | ARTIC ROADRUNNER TOWING SERVICE & W | | | SCAC3 |
| 11 | ACWI | AIRPORT CARGO WAREHOUSE INC | | | SCAC4 |
| 12 | ACWK | AMES, C W INC | | | SCAC4 |
| 13 | ACWL | ACTION LINE TRANSPORT INC | | | SCAC3 |
| 14 | ACWM | ALUMINUM CURTAINWALL SYSTEMS INC | | | SCAC4 |
| 15 | ACWN | AMERICAN COMMERCIAL TOWING COMPANY | | | SCAC3 |
| 16 | ACWO | AMERICAN COMMERCIAL WAREHOUSE INC | | | SCAC3 |
| 17 | ACWP | ACT II (TWO) TRANSPORTATION INC | | | SCAC3 |
| 18 | ACWQ | ATLAS CARTAGE & WAREHOUSE CO INC | | | SCAC3 |
| 19 | ACWR | Aberdeen Carolina & Western Ry. Co. | added 4/1988; eliminated 10/1993; 1/1994 (not listed); eliminated 7/1994; 7/2000-7/2005 | | NAKINA |
| 20 | ACWR | Aberdeen Carolina & Western Ry. Co. | added 4/88; eliminated 10/93; 1/94; eliminated 7/94; 7/2000 | | NRHS |
| 21 | ACWR | ABERDEEN, CAROLINA & WESTERN RAILWAY CO. | | | PWRC |
| 22 | ACWR | Aberdeen, Carolina and Western Railway | | | RSRV |
| 23 | ACWR | ABERDEEN CAROLINA & WESTERN RAILWAY | | | SCAC3 |
| 24 | ACWR | ABERDEEN CAROLINA & WESTERN RAILWAY | | | SCAC4 |
| 25 | ACWR | Aberdeen, Carolina & Western | | CDN | TRAFFIC |
| 26 | ACWT | AM CELL TRUCKING | | | SCAC3 |
| 27 | ACWU | AIGA CONCEPT | | P | BIC |
| 28 | ACWV | A C TOWING AND RECOVERY INC | | | SCAC4 |
| 29 | ACWW | ACE WORLD WIDE MOVING & STORAGE | | | SCAC3 |
| 30 | ACWX | General American Transportation Corp. | 7/1937 (not listed) | | NAKINA |
| 31 | ACWX | American Creosote Works, Inc. (General American Transportation Corp.) | 7/1936 | | NAKINA |
| 32 | ACWX | American Creosote Works, Inc. | 7/1923-7/1935 | | NAKINA |
| 33 | ACWX | *AMERICAN CREOSOTE WORKS | | | PWRC |
| 34 | ACWX | *GENERAL AMERICAN TRANSPORTATION CORP. | | | PWRC |
| 35 | ACWY | ARCHWAY TRANSPORTATION INC | | | SCAC3 |
| 36 | ACWY | ARCHWAY TRANSPORT SERVICES INC | | | SCAC4 |
| 37 | ACWZ | *UNION PACIFIC [CHICAGO & NORTH WESTERN TRANS CO] | | | PWRC |
| 38 | ACWZ | *AMERICAN COLLOID WEST | | | PWRC |
| 39 | ACWZ | Chicago & North Western (Union Pacific Railroad) | | | RSRV |
| 40 | ACWZ | UNION PACIFIC RAILROAD COMPANY | | | SCAC4 |
