| 2301 | ACJR | Ashtabula, Carson and Jefferson Railroad | | | RSRV |
| 2302 | ACJR | ASHTABULA CARSON & JEFFERSON RAILRO | | | SCAC3 |
| 2303 | ACJS | ASTRO COURIER SERVICES | | | SCAC3 |
| 2304 | ACJS | ACE-J TRANSPORTATION INC | | | SCAC4 |
| 2305 | ACJT | ACCENT TRUCKING CORP | | | SCAC3 |
| 2306 | ACJT | ACCENT TRUCKING CORP | | | SCAC4 |
| 2307 | ACJU | AMERICAN COASTAL LINES JOINT VENTURE INC. | | | PWRC |
| 2308 | ACJU | AMERICAN COASTAL LINES, JOINT VENTURE, INC. | | | PWRC |
| 2309 | ACJU | American Coastal Lines Joint Venture | | | RSRV |
| 2310 | ACJU | AMERICAN COASTAL LINES | | | SCAC3 |
| 2311 | ACJW | ASSOCIATED CONTAINER TRANSPORTATION | | | SCAC4 |
| 2312 | ACJY | ASHTABULA CARSON & JEFFERSON RAILROAD | | | PWRC |
| 2313 | ACK | Nantucket Airlines | Callsign: Ack Air, | USA | AVCODES |
| 2314 | ACK | Nantucket Airlines | IATA: DV | | ICAO1 |
| 2315 | ACKA | ABC RACE TRACK TRANSPORT INC | | | SCAC3 |
| 2316 | ACKB | ACTION TRUCK BROKERAGE | | | SCAC3 |
| 2317 | ACKB | ACTION TRUCK BROKERAGE | | | SCAC4 |
| 2318 | ACKC | A C S TRUCKING INC | | | SCAC4 |
| 2319 | ACKD | AROUND THE CLOCK DELIVERY CO INC | | | SCAC3 |
| 2320 | ACKE | AIR CARGO EXPRESS INC | | | SCAC3 |
| 2321 | ACKE | AURORA COOP ELEVATOR COMPANY | | | SCAC4 |
| 2322 | ACKG | A C TRUCKING-LOCAL AND LONG DISTANC | | | SCAC3 |
| 2323 | ACKG | A C TRUCKING INC | | | SCAC4 |
| 2324 | ACKH | ALL CHICAGOLAND MOVING & STORAGE CO | | | SCAC3 |
| 2325 | ACKH | ALL CHICAGOLAND MOVING & STORAGE CO | | | SCAC4 |
| 2326 | ACKI | ACKERS INDUSTRIES INC | | | SCAC3 |
| 2327 | ACKI | ACE TRANSPORT-NC LLC | | | SCAC4 |
| 2328 | ACKJ | A & C TRUCKING 1 LLC | | | SCAC4 |
| 2329 | ACKK | ACCOKEEK EXPRESS INC | | | SCAC3 |
| 2330 | ACKL | ACKLEY TRUCK LINE INC | | | SCAC3 |
| 2331 | ACKM | ACKERMAN OIL CORPORATION | | | SCAC4 |
| 2332 | ACKN | AMERICAN CHEMICAL TANKERS INC | | | SCAC3 |
| 2333 | ACKO | ABC TRUCKING INC | | | SCAC3 |
| 2334 | ACKP | AMERICAN CHECK TRANSPORT INC | | | SCAC3 |
| 2335 | ACKP | ALLIANCE CASKET CORPORATION | | | SCAC4 |
| 2336 | ACKQ | ALL COMMODITIES TRUCKING INC | | | SCAC3 |
| 2337 | ACKQ | ATLANTIC COAST TRUCKING INC | | | SCAC4 |
| 2338 | ACKR | ACTION TRUCK RENTAL | | | SCAC3 |
| 2339 | ACKR | ACKER, BRIAN G | | | SCAC4 |
| 2340 | ACKS | ABLE COURIER SERVICE | | | SCAC3 |
| 2341 | ACKT | ACKERMAN TRUCKING INC | | | SCAC3 |
| 2342 | ACKV | A & C TRUCKING | | | SCAC3 |
| 2343 | ACKV | ACE TANKERS C V | | | SCAC4 |
| 2344 | ACKX | Armstrong Cork Co. | eliminated 1/1966 | | NAKINA |
| 2345 | ACKX | Armstrong Cork Co. | 7/1930-4/1938 | | NAKINA |
| 2346 | ACKX | Armstrong Cork Co., Linoleum Division | 1/1941-7/1965 | | NAKINA |
| 2347 | ACKX | Armstrong Cork Co. | Apr-38 | | NRHS |
| 2348 | ACKX | Armstrong Cork Co., Linoleum Division | 1/52-7/65 | | NRHS |
| 2349 | ACKX | Armstrong Cork Co. | eliminated 1/66 | | NRHS |
| 2350 | ACKX | ARMSTRONG CORK CO. | | | PWRC |
| 2351 | ACKY | ACE TRUCKING COMPANY INC | | | SCAC3 |
| 2352 | ACKY | ARC & D TRUCKING LLC | | | SCAC4 |
| 2353 | ACL | Air Cavrel | Callsign: Cavrel, | GB | AVCODES |
| 2354 | ACL | Transporti Aerei Italiani S.r.l. | IATA: 9X, Callsign: Spada, Name changed to Itali Airlines s.r.l. ICAO designator changed from ACO | I | AVCODES |
| 2355 | ACL | Itali Airlines s.r.l. | IATA: 9X, Callsign: Itali, Name changed from Transporti Aerei Italiani S.r.l. ICAO designator changed from ACO | I | AVCODES |
| 2356 | ACL | Air California | IATA: OC, Callsign: Aircal, Founded in 1967. Merged into American Airlines during 1987. | USA | AVCODES |
| 2357 | ACL | Itali Airlines s.r.l. | IATA: FS, Callsign: Itali, Name changed from Transporti Aerei Italiani S.r.l. ICAO designator changed from ACO | I | AVCODES |
| 2358 | ACL | Aercaribe Aerolina del Caribe, S.A. | IATA: JK, Callsign: Admire, IATA Prefix: 543, Founded in 1997 | CO | AVCODES |
| 2359 | ACL | Itali Airlines | IATA: 9X | | ICAO1 |
| 2360 | ACL | CSX Transportation, Inc. | added 7/1987; 1/1994-7/2005 | | NAKINA |
| 2361 | ACL | Seaboard System R.R., Inc. | added 1/1983; 1/1985; eliminated 7/1987 | | NAKINA |
| 2362 | ACL | Seaboard Coast Line R.R. Co. | 1/1975-1/1980; eliminated 1/1983 | | NAKINA |
| 2363 | ACL | Atlantic Coast Line R.R. Co. | 7/1923-4/1970 | | NAKINA |
| 2364 | ACL | Atlantic Coast Line R.R. Co. | 7/23-4/70 | | NRHS |
| 2365 | ACL | Seaboard Coast Line R.R. Co. | 1/75-1/80; eliminated 1/83 | | NRHS |
| 2366 | ACL | Seaboard System R.R., Inc. | added 1/83; eliminated 7/87 | | NRHS |
| 2367 | ACL | CSX Transportation, Inc. | added 7/87; 1/94-7/2000 | | NRHS |
| 2368 | ACL | CSX TRANSPORTATION, INC. [ATLANTIC COAST LINE; SEABOARD COAST LINE] | | | PWRC |
| 2369 | ACL | Atlantic Coast Line Railroad (CSX Transportation) | | | RSRV |
| 2370 | ACL | Atlantic Coast Line | | USA | TRAFFIC |
| 2371 | ACLB | ASSOCIATED TRANSPORT LINE (BERMUDA) | | | SCAC4 |
| 2372 | ACLC | A C LEASING COMPANY | | | SCAC3 |
| 2373 | ACLD | ACTION LUMBER INC | | | SCAC3 |
| 2374 | ACLE | AMERICAN COACH LINES INC (DC CORP) | | | SCAC3 |
| 2375 | ACLF | AMERICAN COACH LINES INC | | | SCAC3 |
| 2376 | ACLF | AMERI-CAN LOGISTICS LTD | | | SCAC4 |
| 2377 | ACLG | ALL CHICAGO LAND MOVING & STORAGE | | | SCAC3 |
| 2378 | ACLG | AC LOGISTICS LLC | | | SCAC4 |
| 2379 | ACLI | ALLEN, CHARLES L | | | SCAC3 |
| 2380 | ACLI | ASTRO-CHEM LAB INC | | | SCAC4 |
| 2381 | ACLJ | AC STORES AND OIL COMPANY | | | SCAC4 |
| 2382 | ACLK | ACCELL AIR TRANSPORT | | | SCAC3 |
| 2383 | ACLK | AMERICAN COACH LINES OF JACKSONVILL | | | SCAC4 |
| 2384 | ACLL | ALL CAL MOBILE HOME TRANSPORT | | | SCAC3 |
| 2385 | ACLM | ARISTOCRAT LIMOUSINE SERVICE | | | SCAC3 |
| 2386 | ACLN | A-C LOGISTICS (N/K/A GREATWIDE TRAN | | | SCAC4 |
| 2387 | ACLO | AMERICAN COLORS INC | | | SCAC3 |
| 2388 | ACLO | ADVANCE LOGISTICS LLC | | | SCAC4 |
| 2389 | ACLP | AMERICAN CLIPPER TRANSFER & STORAGE | | | SCAC3 |
| 2390 | ACLP | AMERICAN CLIPPER TRANSFER & STORAGE | | | SCAC4 |
| 2391 | ACLQ | ACTION CARTAGE & LEASING CO | | | SCAC3 |
| 2392 | ACLR | ATKKO CARRIERS LLC | | | SCAC4 |
| 2393 | ACLS | AMERICAN COACH LINES OF ORLANDO INC | | | SCAC4 |
| 2394 | ACLS | Atlantic Container Line | Real: ACL | GB | TRAFFIC |
| 2395 | ACLU | ATLANTIC CONTAINER LINE | | USA | BIC |
| 2396 | ACLU | ATLANTIC CONTAINER LINE LTD | | | PWRC |
| 2397 | ACLU | Atlantic Container Line | | | RSRV |
| 2398 | ACLU | ATLANTIC CONTAINER LINES LTD | | | SCAC3 |
| 2399 | ACLU | ATLANTIC CONTAINER LINE AB | | | SCAC4 |
| 2400 | ACLV | AMERICAN CONTINENTAL VAN LINES INC | | | SCAC3 |
