| 1 | UH | Eurasia Aircompany, JSC | ICAO: EUS, Callsign: Eurasia, IATA Prefix: 914, | RUS | AVCODES |
| 2 | UH | Bristow Helicopters Group Ltd. | ICAO: BHL, Callsign: Bristow, Desigantor UH recalled by IATA | GB | AVCODES |
| 3 | UH | U.S. Helicopter Corporation | ICAO: USH, Callsign: US Heli, Founded in 2004. Ceased operations on 25 September 2009. | USA | AVCODES |
| 4 | UH | AtlasJet Ukraine | ICAO: UJX, Callsign: Atlas Ukraine, IATA Prefix: 500, Ceased operations. | UA | AVCODES |
| 5 | UH | Jet Exchange Limited | ICAO: XCH, Callsign: Exchange, | GB | AVCODES |
| 6 | UHAM | UNIVERSAL HANDLING EQUIPMENT COMPAN | | | SCAC4 |
| 7 | UHC | Ukrainian Handling Company LLC | Callsign: Handling Company, | UA | AVCODES |
| 8 | UHCA | UNITED HAULING CORP | | | SCAC4 |
| 9 | UHE | Unidad de Helicopteros de la Ertzaintza | | E | AVCODES |
| 10 | UHER | UHER TRUCKING INC | | | SCAC4 |
| 11 | UHI | Unicorn Air Charter Services | | GH | AVCODES |
| 12 | UHIG | UNITED HIGHWAYS INC | | | SCAC4 |
| 13 | UHJF | UTAH STEP SAVER | | | SCAC4 |
| 14 | UHL | Ukrainian Helicopters, CJS Company | Callsign: Ukraine Copters, Name changed to Aviation Company Ukrainian Helicopters. | UA | AVCODES |
| 15 | UHL | Aviation Company Ukrainian Helicopters | Callsign: Ukraine Copters, Name changed from Ukrainian Helicopters, CJS Company. | UA | AVCODES |
| 16 | UHL | Ukrainian Helicopters | | | ICAO1 |
| 17 | UHL | G.Uhlmann GmbH | | DE | VKM |
| 18 | UHLG | UHU TRUCKING | | | SCAC4 |
| 19 | UHLH | UNITED HEIRS LLC | | | SCAC4 |
| 20 | UHLI | UHLIK TRANSPORT INC | | | SCAC4 |
| 21 | UHLU | UNIT HIRE LIMITED | | GB | BIC |
| 22 | UHMU | HIMMAGISTRAL LTD | | RUS | BIC |
| 23 | UHO | LLC H3Operations | Callsign: Heliops, | UA | AVCODES |
| 24 | UHP | United Air Service | Callsign: Sierra Yankee, Designator SY recalled by IATA | WAN | AVCODES |
| 25 | UHP | United Air Service | IATA: SY, Callsign: Sierra Yankee, Designator SY recalled by IATA | WAN | AVCODES |
| 26 | UHRX | Upper Hudson River R.R. Corp. | 7/2000 (not listed); added 1/2003; eliminated 4/2003; 7/2005 (not listed) | | NAKINA |
| 27 | UHRX | Upper Hudson River R.R. Corp. | Jul-00 | | NRHS |
| 28 | UHRX | UPPER HUDSON RIVER RAILROAD | | | PWRC |
| 29 | UHRX | Upper Hudson River Railroad | | | RSRV |
| 30 | UHRX | UPPER HUDSON RIVER RAILROAD CORPORA | | | SCAC4 |
| 31 | UHS | Ulyanovsk Higher Civil Aviation School | Callsign: Pilot Air, | RUS | AVCODES |
| 32 | UHS | Ulyanovsk Higher Civil Aviation School | | | ICAO1 |
| 33 | UHSL | ULTRA HIGH SPECIALTIES LLC | | | SCAC4 |
