| 301 | YLLJ | YUSEN LOGISTICS (JAPAN) CO LTD | | | SCAC4 |
| 302 | YLLO | YELLOW CAB TRANSFER | | | SCAC1 |
| 303 | YLLW | YELLOW RIVER FARMS INC | | | SCAC4 |
| 304 | YLOG | YUANMAO LOGISTICS | | | SCAC4 |
| 305 | YLRR | YUSEN LOGISTICS (AMERICAS) INC (REV | | | SCAC4 |
| 306 | YLST | YELLOWSTONE BEAN COMPANY | | | SCAC4 |
| 307 | YLSV | YARD LINK SERVICES | | | SCAC4 |
| 308 | YLTG | YULE, J R TRUCKING INC | | | SCAC4 |
| 309 | YLTN | YELTON TRUCKING COMPANY INC | | | SCAC4 |
| 310 | YLTP | YELLOW LINE TRANSPORTATION | | | SCAC4 |
| 311 | YLTR | YELLOW TRANSPORTATION | | | SCAC4 |
| 312 | YLUS | YUSEN LOGISTICS (AMERICAS) INC (US | | | SCAC4 |
| 313 | YLWS | YELLOWSTONE LOGISTICS INC | | | SCAC4 |
| 314 | YM | Compass Airlines | ICAO: CYM, Callsign: Compair, Founded in 1990 ceased operations in 1991. Restarted operations in 1992 and finally ceased operations on 22 March 1993. | AUS | AVCODES |
| 315 | YM | Montenegro Airlines | ICAO: MGX, Callsign: Montair, IATA Prefix: 409, IATA designator changed from 1I | YU | AVCODES |
| 316 | YM | Dirac Aviation | ICAO: DAV, Callsign: Dirac, | F | AVCODES |
| 317 | YM | Montenegro Airlines | ICAO: MGX, Callsign: Montair, IATA Prefix: 409, IATA designator changed from 1I | SCG | AVCODES |
| 318 | YM | Montenegro Airlines | ICAO: MGX, Callsign: Montair, IATA Prefix: 409, Ceased operations in 25 December 2020. IATA designator changed from 1I | CG | AVCODES |
| 319 | YMBH | YMC TRANSPORT | | | SCAC4 |
| 320 | YMBU | P & O FERRYMASTERS LTD | | B | BIC |
| 321 | YMCI | YOUNG MANUFACTURING COMPANY INC | | | SCAC4 |
| 322 | YMCK | YMC TRUCKING | | | SCAC4 |
| 323 | YMCM | YOUNGS MARKET COMPANY | | | SCAC4 |
| 324 | YMCY | YURIMUNI COMPANY | | | SCAC4 |
| 325 | YMCZ | YANGMING MARINE TRANSPORT CORPORATION | | | PWRC |
| 326 | YMCZ | Yangming Marine Transport Corporation | | | RSRV |
| 327 | YMCZ | YANGMING MARINE TRANSPORT CORPORATI | | | SCAC4 |
| 328 | YMED | YAMASHI | | | SCAC4 |
| 329 | YMGT | Y M GROUP INC | | | SCAC4 |
| 330 | YMGU | CENTRE DE RENOVATION MARCEL DAGORT | | F | BIC |
| 331 | YMGU | Y M C G SRL | | | SCAC4 |
| 332 | YMIP | YELLOW MOUNTAIN IMPORTS | | | SCAC4 |
| 333 | YMLU | YANG MING MARINE TRANSPORT CORP. | | RC | BIC |
| 334 | YMLU | YANGMING MARINE TRANSPORT CORPORATION | | | PWRC |
| 335 | YMLU | Yangming Marine Transport Corporation | | | RSRV |
| 336 | YMLU | YANGMING MARINE TRANSPORT CORP | | | SCAC1 |
| 337 | YMLU | YANG MING MARINE TRANSPORT CORP | | | SCAC4 |
| 338 | YMLZ | YANGMING MARINE TRANSPORT CORPORATION | | | PWRC |
| 339 | YMLZ | Yangming Marine Transport Corporation | | | RSRV |
| 340 | YMLZ | YANGMING MARINE TRANSPORT CORPORATI | | | SCAC4 |
| 341 | YMMU | YANG MING MARINE TRANSPORT CORP. | | RC | BIC |
| 342 | YMNS | YAMATO ENGINES SPECIALISTS 1990 LTD | | | SCAC4 |
| 343 | YMQZ | YELLOW MEDICAN QUARRY | | | PWRC |
| 344 | YMRC | Yokohama Minatomirai Railway Corporation | | J | TRAFFIC |
| 345 | YMRJ | YAGOD, MAIER - REED, JON | | | SCAC4 |
| 346 | YMRU | YANMAR | | | SCAC4 |
| 347 | YMSP | YARMOUTH SEA PRODUCTS LTD | | | SCAC4 |
| 348 | YMTC | Y & M TRUCKING COMPANY | | | SCAC4 |
| 349 | YMVS | YUCCA MOVING & STORAGE INC | | | SCAC4 |
| 350 | YN | Air Creebec (1994), Inc. | ICAO: CRQ, Callsign: Cree, IATA Prefix: 219, | CDN | AVCODES |
| 351 | YN | Youngstown and Northern R.R. Co. | 1/1975-1/1980; eliminated 1/1981; eliminated 7/1981 | | NAKINA |
| 352 | YN | Youngstown and Northern R.R. Co. | 1/75-1/80; eliminated 1/81; eliminated 7/81 | | NRHS |
| 353 | YN | YOUNGSTOWN & NORTHERN RAILROAD CO. | | | PWRC |
| 354 | YN | Youngstown and Northern R.R. Co. | | USA | TRAFFIC |
| 355 | YNBL | YANOSAN INC | | | SCAC4 |
| 356 | YNDR | YONDER FRUIT FARMS, INC. | | | SCAC4 |
| 357 | YNGC | YOUNGS COMMERCIAL TRANSFER INC | | | SCAC4 |
| 358 | YNGG | YONGS TRUCKING COMPANY | | | SCAC4 |
| 359 | YNGH | YOUNGS FUEL SERVICE | | | SCAC4 |
| 360 | YNGT | YOUNG TRANS CO | | | SCAC4 |
| 361 | YNGW | YOUNG & SONS WHOLESALE DISTRIBUTORS | | | SCAC4 |
| 362 | YNHK | YANGTZE NAVIGATION HK CO LTD | | | SCAC4 |
| 363 | YNKG | YONKES TRUCKING | | | SCAC4 |
| 364 | YNKT | YANKE, N TRANSFER LTD | | | SCAC4 |
| 365 | YNMS | YOUNG MOVING & STORAGE INC | | | SCAC4 |
| 366 | YNRC | YERENA ARAUZ, RAMON | | | SCAC4 |
| 367 | YNTR | YACYSHYN TRUCKING LTD | | | SCAC4 |
| 368 | YO | Heli Air Monaco | ICAO: MCM, Callsign: Heli Air, IATA Prefix: 747, | MC | AVCODES |
| 369 | YOAW | YOURS TRANSPORT INC | | | SCAC4 |
| 370 | YOCI | YORKSTON OIL CO INC | | | SCAC4 |
| 371 | YOCX | Yale Oil Corp. | 7/1923-7/1935 | | NAKINA |
| 372 | YOCX | Yale Oil Association | 7/1937-1/1943 | | NAKINA |
| 373 | YOCX | Union Tank Car Co. | 1/1945 (not listed) | | NAKINA |
| 374 | YOCX | YALE OIL ASSOCIATION (UUNION TANK CAR CO.) | | | PWRC |
| 375 | YODA | D&D Sexton | | | SCAC2 |
| 376 | YODD | YODER, DENNIS TRANSPORT INC | | | SCAC4 |
| 377 | YODO | YOUNG, DANIEL F INC | | | SCAC4 |
| 378 | YODR | YOUNG OIL INC | | | SCAC4 |
| 379 | YOG | Central Aviation, Inc. | Callsign: Yogan Air, | USA | AVCODES |
| 380 | YOG | Central Aviation | | | ICAO1 |
| 381 | YOGI | YOGIS TRUCKING | | | SCAC4 |
| 382 | YOIK | YORK OIL INC | | | SCAC4 |
| 383 | YOIL | YODER OIL INC | | | SCAC4 |
| 384 | YOIU | TRITON CONTAINER INTERNATIONAL LTD | | BM | BIC |
| 385 | YOIU | Triton Container International | | | RSRV |
| 386 | YOIU | TRITON CONTAINER INTERNATIONAL CORP | | | SCAC4 |
| 387 | YOJC | YOUNG, J C | | | SCAC4 |
| 388 | YOKH | YOUNATHAN, KHANNA (K Y) | | | SCAC4 |
| 389 | YOKOK | Yokokawa Bus | | J | TRAFFIC |
| 390 | YOKX | Yale Oil Association | 4/1938 | | NAKINA |
| 391 | YOKX | Yale Oil Association | Apr-38 | | NRHS |
| 392 | YOKX | YALE OIL ASSOCIATION | | | PWRC |
| 393 | YOLA | MP Trolleybusniy Transport, Yoshkar-Ola | | RUS | TRAFFIC |
| 394 | YOLU | CARU GOLDGIE CONTAINERS CO., LTD. | | HK | BIC |
| 395 | YOMI | YEE ON MANAGEMENT INC | | | SCAC4 |
| 396 | YOMT | YO-MAC TRANSPORT INC | | | SCAC4 |
| 397 | YONC | YONKE CHUY | | | SCAC4 |
| 398 | YONG | YOUNG, DONALD TRANSPORT INC | | | SCAC4 |
| 399 | YONK | Yonkers Transit | | US-NY | TRAFFIC |
| 400 | YORF | YOR FOOD SERVICE INC | | | SCAC4 |
