| 1 | UF | Ukrainian Mediterranean Airlines Ltd. | ICAO: UKM, Callsign: Ukraine Mediterranee, IATA Prefix: 828, | UA | AVCODES |
| 2 | UF | Air Sardinia S.p.A. | ICAO: ASZ, | I | AVCODES |
| 3 | UF | Universal Flying Services Ltd. | Callsign: Universal, | GB | AVCODES |
| 4 | UF | Petroleum Air Services | ICAO: PER, Callsign: Pas Air, The airline was established and started operations in 1982 | ET | AVCODES |
| 5 | UF | Ukraine Mediterranean Airlines Ltd t/a UM Air Airlines | ICAO: UKM, Callsign: Ukraine Mediterranee, IATA Prefix: 828, Ceased operation during 2018. | UA | AVCODES |
| 6 | UF | Union Freight | | USA | TRAFFIC |
| 7 | UFA | State Flight Academy Of Ukraine, The | Callsign: Flight Academy, | UA | AVCODES |
| 8 | UFA | State Flight Academy of Ukraine | | | ICAO1 |
| 9 | UFA | PATP1 Ufa | | RUS | TRAFFIC |
| 10 | UFA | UFA AG | | CH | VKM |
| 11 | UFAB | U-FAB BOATS | | | SCAC4 |
| 12 | UFAE | UFA EXPRESS INC | | | SCAC4 |
| 13 | UFBI | UNI-FAB | | | SCAC4 |
| 14 | UFBK | UNITED FREIGHT BROKERAGE INC | | | SCAC4 |
| 15 | UFBN | ULTRAFAB INC | | | SCAC4 |
| 16 | UFC | UNITED FRUIT CO | | | PWRC |
| 17 | UFCC | FLEXI-VAN LEASING, INC. | | | PWRC |
| 18 | UFCH | ULTIMATE FIGHTING CHAMPIONSHIP | | | SCAC4 |
| 19 | UFCN | UNI FIRST CORPORATION | | | SCAC4 |
| 20 | UFCQ | UNIVERSAL FREIGHT CORP | | | SCAC4 |
| 21 | UFCU | SEACO SRL | | BDS | BIC |
| 22 | UFCU | FLEXI-VAN LEASING, INC. | | | PWRC |
| 23 | UFCU | Flexi-Van Leasing | | | RSRV |
| 24 | UFCU | GENSTAR CONTAINER CORPORATION | | | SCAC4 |
| 25 | UFCY | ULTIMATE FREIGHT COMPANY | | | SCAC4 |
| 26 | UFCZ | *FLEXI-VAN LEASING, INC. | | | PWRC |
| 27 | UFCZ | *U. S. FUEL CO. | | | PWRC |
| 28 | UFCZ | Flexi-Van Leasing | | | RSRV |
| 29 | UFDI | UNIQUE FINISHING AND DISTRIBUTION I | | | SCAC4 |
| 30 | UFEE | UNIFEEDER | | | SCAC4 |
| 31 | UFEL | US FREIGHT EXPRESS LLC | | | SCAC4 |
| 32 | UFEQ | US FREIGHT EXPEDITORS CO INC | | | SCAC4 |
| 33 | UFFC | US FREIGHT FINDERS INC | | | SCAC4 |
| 34 | UFFI | UNITED FORCE FREIGHT INC | | | SCAC4 |
| 35 | UFFN | UNITED FREIGHT FORWARDERS INC | | | SCAC4 |
| 36 | UFFW | UNIVERSAL FREIGHT FORWARDERS LTD | | | SCAC4 |
| 37 | UFGC | US FREIGHT LLC | | | SCAC4 |
| 38 | UFGL | UNIFIED GLOBAL LOGISTICS INC | | | SCAC4 |
| 39 | UFGX | United Fuel Gas Co. | 8/1920-7/1923; 1/1952-7/1954; eliminated 10/1954 | | NAKINA |
| 40 | UFGX | United Fuel Gas Co. | Jan-52 | | NRHS |
| 41 | UFGX | UNITED FUEL GAS CO. | | | PWRC |
| 42 | UFHD | UNITED FISH DISTRIBUTORS INC | | | SCAC4 |
| 43 | UFHL | UPPAL FREIGHTS LTD | | | SCAC4 |
| 44 | UFI | Umbria Fly | Callsign: Umbria Fly, | I | AVCODES |
| 45 | UFIC | US FREIGHTWAYS INC | | | SCAC4 |
| 46 | UFIX | Utility Fuels, Inc. | added 7/1978; 1/1980-1/1994; eliminated 4/1994 | | NAKINA |
| 47 | UFIX | Houston Lighting & Power Co. | added 4/1994; eliminated 7/2000 | | NAKINA |
| 48 | UFIX | Reliant Energy HL&P | added 7/2000; 7/2000; eliminated 10/2004 | | NAKINA |
| 49 | UFIX | Texas Genco, LP | added 10/2004; eliminated 7/2005 | | NAKINA |
| 50 | UFIX | Texas Genco II, LP | added 7/2005; 7/2005; eliminated 10/2006 | | NAKINA |
| 51 | UFIX | NRG Energy, Inc. | added 10/2006; eliminated 4/2009; eliminated 7/2009 | | NAKINA |
| 52 | UFIX | Utility Fuels, Inc. | added 7/78; 1/80-1/94; eliminated 4/94 | | NRHS |
| 53 | UFIX | Houston Lighting & Power Co. | added 4/94; eliminated 7/2000 | | NRHS |
| 54 | UFIX | Reliant Energy HL&P | added 7/2000; 7/2000 | | NRHS |
| 55 | UFIX | *UTILITY FUELS INC. | | | PWRC |
| 56 | UFIX | +NRG ENERGY, INC. [TEXAS GENCO; [RELIANT ENERGY; HOUSTON LIGHTING & POWER COMPANY] | | | PWRC |
| 57 | UFIX | Utility Fuels | | | RSRV |
| 58 | UFIX | NRG ENERGY INC | | | SCAC4 |
| 59 | UFIZ | U.F.I. CORP | | | PWRC |
| 60 | UFL | Unifly | Callsign: Unifly, | GQ | AVCODES |
| 61 | UFLD | UNITED FLORAL DISTRIBUTORS | | | SCAC4 |
| 62 | UFLF | UNIQUE FREIGHT LINES INC | | | SCAC4 |
| 63 | UFLG | UNITED FREIGHT & LOGISTICS LTD | | | SCAC4 |
| 64 | UFLQ | UNITED FUEL LINES INC | | | SCAC4 |
| 65 | UFLR | UNITED FREIGHT LOGISTICS LLC | | | SCAC4 |
| 66 | UFLS | UF LOGISTICS INC | | | SCAC4 |
| 67 | UFO | Ateliers d\'Orval | | FR | VKM |
| 68 | UFOL | UNITED FUEL OIL | | | SCAC4 |
| 69 | UFPD | UNITED FRUIT & PRODUCE CO | | | SCAC4 |
| 70 | UFPM | UFP TRANSPORTATION INC | | | SCAC4 |
| 71 | UFPZ | UNIVERSAL FOREST PRODUCTS | | | PWRC |
| 72 | UFR | United Africa Airline (Liberia), Inc. | Callsign: United Africa, | LB | AVCODES |
| 73 | UFR | UNIFERTRANS S.A. | | RO | VKM |
| 74 | UFRE | U S FREIGHT INC | | | SCAC4 |
| 75 | UFRM | UNITED FARMERS COOPERATIVE | | | SCAC4 |
| 76 | UFRS | UNITED FREIGHT SERVICE INC | | | SCAC4 |
| 77 | UFS | UFS, Inc. | IATA: U2, Callsign: Feeder Flight, Founded in 1993. Ceased operations during 1999. | USA | AVCODES |
| 78 | UFS | UFS | | | ICAO1 |
| 79 | UFSI | UNIVERSAL FREIGHT SYSTEMS INC | | | SCAC4 |
| 80 | UFSK | US FREIGHT SYSTEMS INC | | | SCAC4 |
| 81 | UFSL | URBAN FREIGHT SERVICES LTD | | | SCAC4 |
| 82 | UFSP | UNLIMITED FURNITURE SUPPLY INC | | | SCAC4 |
| 83 | UFSQ | UNION FREIGHT SERVICES INC | | | SCAC4 |
| 84 | UFSS | CHIQUITA BRANDS, INC. | | | SCAC4 |
| 85 | UFSV | USA FREIGHT SERVICE INC | | | SCAC4 |
| 86 | UFSY | UNIVERSAL FREIGHT SYSTEM | | | SCAC4 |
| 87 | UFT | UniferTrans | | RO | TRAFFIC |
| 88 | UFTA | UNITED FREIGHT TRANSPORT LLC | | | SCAC4 |
| 89 | UFTI | UF TRUCKING INC | | | SCAC4 |
| 90 | UFTP | UNITED FREIGHT & TRANSPORT INC | | | SCAC4 |
| 91 | UFTQ | UNION FREIGHTWAYS, INC | | | SCAC1 |
| 92 | UFTQ | UNION FREIGHTWAYS CARRIERS LTD | | | SCAC4 |
| 93 | UFTU | UNIVERSAL FREIGHT CARRIERS, INC. | | | SCAC4 |
| 94 | UFTX | Residco | added 7/2008 | | NAKINA |
| 95 | UFTX | RESIDCO | | | PWRC |
| 96 | UFTX | RESIDCO | | | SCAC4 |
| 97 | UFXG | ULTRAFLEX AGENCY S A | | | SCAC4 |
