| 1 | NH | All Nippon Airways Co. Ltd. | ICAO: ANA, Callsign: All Nippon, IATA Prefix: 205, | J | AVCODES |
| 2 | NH | Consolidated Rail Corp. | added 4/1976; 1/1980-1/1994; eliminated 7/1999 | | NAKINA |
| 3 | NH | Penn Central Transportation Co., Robert W. Blanchette, Richard C. Bond and John H. McArthur, Trustees | eliminated 4/1976 | | NAKINA |
| 4 | NH | Penn Central Transportation Co. | 1/1975 | | NAKINA |
| 5 | NH | New York, New Haven & Hartford R.R. Co. | 8/1920-10/1966 | | NAKINA |
| 6 | NH | New York, New Haven & Hartford R.R. Co. | 4/38-10/66 | | NRHS |
| 7 | NH | Penn Central Transportation Co. | Jan-75 | | NRHS |
| 8 | NH | Penn Central Transportation Co., Robert W. Blanchette, Richard C. Bond and John H. McArthur, Trustees | eliminated 4/76 | | NRHS |
| 9 | NH | Consolidated Rail Corp. | added 4/76; 1/80-1/94; eliminated 7/99 | | NRHS |
| 10 | NH | CONSOLIDATED RAIL CORP. [PENN CENTRAL TRANSPORTATION; NEW YORK, NEW HAVEN & HARTFORD RR] | | | PWRC |
| 11 | NH | New York, New Haven and Hartford Railroad (CSX Transportation) | | | RSRV |
| 12 | NH | New Heaven | | USA | TRAFFIC |
| 13 | NH&W | New River, Holston & Western R.R. (Norfolk & Western Ry.) | 8/1920-7/1923 | | NAKINA |
| 14 | NH&W | NORFOLK & WESTERN RWY. [NEW RIVER, HOLSTON & WESTERN RAILROAD] | | | PWRC |
| 15 | NHA | Air Nove | Callsign: Air Nove, | BG | AVCODES |
| 16 | NHA | Nantucket Shuttle/Horizon Air Charter, Inc. | Callsign: Shuttleflight, ICAO designator changed from NKT | USA | AVCODES |
| 17 | NHAG | NANCYS HAULING | | | SCAC4 |
| 18 | NHAL | NAHAL TRUCKING | | | SCAC4 |
| 19 | NHAM | NORTH AMERICAN TRANSPORTATION INC | | | SCAC4 |
| 20 | NHAP | NELSON, HARPER | | | SCAC4 |
| 21 | NHAT | NATI INC. | | | SCAC4 |
| 22 | NHBC | NEW HOLLAND BULK CARRIERS LLC | | | SCAC4 |
| 23 | NHBL | NEW HAMPSHIRE BUS LINES INC | | | SCAC3 |
| 24 | NHBS | NEW HAVEN BUS SERVICE INC | | | SCAC3 |
| 25 | NHBT | NORWICH BRICK & TILE | | | SCAC4 |
| 26 | NHC | Northern Helicopter GmbH | Callsign: Northern, | D | AVCODES |
| 27 | NHC | | | CZ | TRAFFIC |
| 28 | NHCA | NASH-CAN AGENCY CORP | | | SCAC4 |
| 29 | NHCD | NATIONAL HIGHWAY CARRIERS DIRECTORY | | | SCAC3 |
| 30 | NHCF | NORTH HAVEN CARLOADING | | | SCAC3 |
| 31 | NHCF | NORTH COUNTRY FUR | | | SCAC4 |
| 32 | NHCI | NORTHERN ILLINOIS COIN & STAMP INC | | | SCAC4 |
| 33 | NHCL | NICHOLSON & HALL CORPORATION | | | SCAC4 |
| 34 | NHCM | NORSK HYDRO CRUDE MARKETING INC | | | SCAC4 |
| 35 | NHCN | NORTHERN HAULERS CORP. | | | PWRC |
| 36 | NHCO | NEW HAVEN COLONY FARMS LTD | | | SCAC4 |
| 37 | NHCP | NORTH HILL CORPORATION | | | SCAC4 |
| 38 | NHCR | New Hampshire Central R.R., Inc. | added 10/1993; 1/1994; eliminated 4/1995; 7/2000-7/2005 | | NAKINA |
| 39 | NHCR | New Hampshire Central R.R., Inc. | added 10/93; 1/94; eliminated 4/95; 7/2000 | | NRHS |
| 40 | NHCR | NEW HAMPSHIRE CENTRAL RAILROAD, INC. | | | PWRC |
| 41 | NHCR | New Hampshire Central Railroad | | | RSRV |
| 42 | NHCR | NEW HAMPSHIRE CENTRAL RAILROAD INC | | | SCAC4 |
| 43 | NHCS | NEW HORIZONS CHARTER SERVICE | | | SCAC3 |
| 44 | NHCU | MITSUI & CO LTD | | J | BIC |
| 45 | NHCU | NIHON HELIUM INC | | | SCAC4 |
| 46 | NHD | NHV A/S | Callsign: Nemo, | DK | AVCODES |
| 47 | NHDI | N H D INC | | | SCAC3 |
| 48 | NHDI | NASH, EDDIE & SONS INC | | | SCAC4 |
| 49 | NHDX | NEW HAMPSHIRE DEPARTMENT OF TRANSPORTATION | | | PWRC |
| 50 | NHE | Nord Helikopter | Callsign: Nord, | N | AVCODES |
| 51 | NHEC | NATIONAL HIGHWAY ENTERPRISES INC | | | SCAC4 |
| 52 | NHEL | N H E LEASING | | | SCAC3 |
| 53 | NHEL | N H E LEASING | | | SCAC4 |
| 54 | NHEN | NIGHTHAWK ENTERPRISES INC | | | SCAC4 |
| 55 | NHEQ | NATIONAL HIGHWAY EQUIPMENT INC | | | SCAC3 |
| 56 | NHEQ | NORTHERN INTERIORS | | | SCAC4 |
| 57 | NHEU | NEFTECHIMECO LTD | | | SCAC4 |
| 58 | NHG | NHT Lineas Aereas | IATA: N7, Name changed to Brava Linhas Aereas | BR | AVCODES |
| 59 | NHG | Brava Linhas Aereas | IATA: N7, Name changed from NHT Lineas Aereas | BR | AVCODES |
| 60 | NHG | NHT Lineas Aereas | | | ICAO1 |
| 61 | NHGL | NEW HOPE GLOBAL LOGISTICS | | | SCAC4 |
| 62 | NHGR | NORTHANGER SHIPPING CORPORATION | | | SCAC3 |
| 63 | NHGS | NOB HILL GERNERAL STORE INC | | | SCAC3 |
| 64 | NHGX | New Haven Gas Light Co. | 7/1930-1/1943 | | NAKINA |
| 65 | NHGX | New Haven Gas Light Co. | Apr-38 | | NRHS |
| 66 | NHGX | NEW HAVEN GAS LIGHT CO. | | | PWRC |
| 67 | NHIC | NH-HAY INC | | | SCAC4 |
| 68 | NHIM | NASIM HOME | | | SCAC4 |
| 69 | NHIN | NU HOT INC | | | SCAC4 |
| 70 | NHIR | New Hope & Ivyland R.R. Co. | added 10/1989; eliminated 10/1991 | | NAKINA |
| 71 | NHIR | New Hope & Ivyland R.R. Co., McHugh Brothers Heavy Hauling Inc. — Operator & Lessee | added 7/1980; eliminated 10/1989 | | NAKINA |
| 72 | NHIR | New Hope & Ivyland R.R. Co. | 1/1975-1/1980; eliminated 7/1980 | | NAKINA |
| 73 | NHIR | New Hope & Ivyland R.R. Co. | 1/75-1/80; eliminated 7/80 | | NRHS |
| 74 | NHIR | New Hope & Ivyland R.R. Co., McHugh Brothers Heavy Hauling Inc. -- Operator & Lessee | added 7/80; eliminated 10/89 | | NRHS |
| 75 | NHIR | New Hope & Ivyland R.R. Co. | added 10/89; eliminated 10/91 | | NRHS |
| 76 | NHIR | RETIRED 07-31-91 ATP (585) [NEW HOPE & IVYLAND RAILROAD] | | | PWRC |
| 77 | NHIR | New Hope & Ivyland Railroad Company | | USA | TRAFFIC |
| 78 | NHIU | NIPPON GASES NORGE AS | | N | BIC |
| 79 | NHIU | HYDRO GAS AND CHEMICALS AS | | | SCAC4 |
| 80 | NHIX | Merchants Despatch Transportation Corp. | added 7/1962; 7/1965; eliminated 7/1966 | | NAKINA |
| 81 | NHIX | Northern Refrigerator Line, Inc. | 4/1947-4/1961; eliminated 7/1962 | | NAKINA |
| 82 | NHIX | Northern Refrigerator Line, Inc. | 1/52-4/61 | | NRHS |
| 83 | NHIX | Merchants Despatch Transportation Corp. | 7/65; eliminated 7/66 | | NRHS |
| 84 | NHIX | *NORTHERN REFRIGERATOR LINE INC. | | | PWRC |
| 85 | NHIX | *MERCHANTS DESPATCH TRANSPORTATION CORP. | | | PWRC |
| 86 | NHK | Federal Aviation Administration (ATO-330) | Callsign: Nighthawk, Name changed to United States Government, Federal Aviation Administration. | USA | AVCODES |
| 87 | NHK | United States Government, Federal Aviation Administration | Callsign: Nighthawk, Name changed from Federal Aviation Administration (ATO-330). | USA | AVCODES |
| 88 | NHK | Federal Aviation Administration | | | ICAO1 |
| 89 | NHKA | NHK ENTERPRISES AMERICA INC | | | SCAC4 |
| 90 | NHKC | NIGHTHAWK COURIER SERVICE INC | | | SCAC3 |
| 91 | NHKE | NIGHTHAWK ENTERPRISES | | | SCAC3 |
| 92 | NHKF | NIGHTHAWK FLATBED TRANSPORT | | | SCAC4 |
| 93 | NHKT | NIGHT HAWK TRANSPORT INC | | | SCAC3 |
| 94 | NHL | Northumbria Helicopters Limited | Callsign: Northumbria, | GB | AVCODES |
| 95 | NHL | Northumbria Helicopters | | | ICAO1 |
| 96 | NHLA | NEWTOWN HOLDINGS LTD | | | SCAC4 |
| 97 | NHLE | NIHLES TRUCKING | | | SCAC3 |
| 98 | NHLG | NORTH IDAHO ENERGY LOGS INC | | | SCAC4 |
| 99 | NHLI | N H L INC | | | SCAC3 |
| 100 | NHLI | NEWHOPE LOGISTICS INC | | | SCAC4 |
