| 1 | DK | Premiair A/S | ICAO: VKG, Callsign: Viking, IATA Prefix: 630, Name changed to MyTravel Airways A/S w.e.f. 01 May 2002. | DK | AVCODES |
| 2 | DK | Eastland Air | ICAO: ELA, | AUS | AVCODES |
| 3 | DK | Air Corse | ICAO: ARK, Callsign: Air Corse, | F | AVCODES |
| 4 | DK | Scanair | ICAO: VKG, Callsign: Sunjet, Founded in 1961. Merged with Conair of Scandinavia to from Premiair A/S 0n 01 January 1994. | DK | AVCODES |
| 5 | DK | MyTravel Airways A/S | ICAO: VKG, Callsign: Viking, IATA Prefix: 630, Name changed to Thomas Cook Airlines Scandinavia A/S. Name changed from Premiair A/S on 01 May 2002. | DK | AVCODES |
| 6 | DK | Thomas Cook Airlines Scandinavia A/S | ICAO: VKG, Callsign: Viking, IATA Prefix: 630, Name changed to SunClass Airlines A/S w.e.f 30 October 2019. Name changed from MyTravel Airways A/S. Name changed from Premiair A/S 01 May 2002. | DK | AVCODES |
| 7 | DK | SunClass Airlines ApS | ICAO: VKG, Callsign: Viking, IATA Prefix: 630, Name changed from Thomas Cook Airlines Scandinavia A/S w.e.f. 30 October 2019 and previously from MyTravel Airways A/S. Name changed from Premiair A/S 01 May 2002. | DK | AVCODES |
| 8 | DK | Dampfbahnfreunde Kahlgrund e.V. | Hanau | D | privat-bahn.de |
| 9 | DK&W | DeKalb & Western R.R. Co. | 7/1923-7/1936 | | NAKINA |
| 10 | DK&W | DeKalb & Western R.R. Co. | 23-Jul | | NRHS |
| 11 | DK&W | DEKALB & WESTERN RAILROAD CO. | | | PWRC |
| 12 | DKA | Daka | | KZ | AVCODES |
| 13 | DKA | Daka | | | ICAO1 |
| 14 | DKA | DAKOTA BUS SERVICE INC | | | SCAC4 |
| 15 | DKAC | DUKES AUTO TRUCK INC | | | SCAC4 |
| 16 | DKAD | DAJE TRUCKING INC | | | SCAC4 |
| 17 | DKAE | DEAN, KAY TRADING | | | SCAC4 |
| 18 | DKAU | ACIDEKA SA | | | SCAC4 |
| 19 | DKAY | DOLGY, KATHERINE | | | SCAC4 |
| 20 | DKB | Dürener Kreisbahn GmbH | Düren | D | privat-bahn.de |
| 21 | DKB | Dürener Kreisbahn | | D | TRAFFIC |
| 22 | DKB | Dürener Kreisbahn | | DE | VKM |
| 23 | DKBE | DKB ENTERPRISES LTD | | | SCAC4 |
| 24 | DKBF | DKB FARMS AND SERVICES LLC | | | SCAC4 |
| 25 | DKBM | Dampf-Kleinbahn Mühlenstroth | | D | TRAFFIC |
| 26 | DKBR | DEKALB RECOVERY INC | | | SCAC4 |
| 27 | DKBT | DAKOTA BELLE LLC | | | SCAC4 |
| 28 | DKCG | DOUBLE KC TRUCKING INC | | | SCAC4 |
| 29 | DKCH | DUKO OIL CO INC | | | SCAC4 |
| 30 | DKCK | DOLLAR TRUCKING INC | | | SCAC4 |
| 31 | DKCO | DAIO KAIUN CO LTD | | | SCAC4 |
| 32 | DKCQ | DOSCH-KING CO INC | | | SCAC4 |
| 33 | DKCR | DAKOTA CARRIERS INC | | | SCAC4 |
| 34 | DKCS | DERICK, C TRANSPORT INC | | | SCAC4 |
| 35 | DKCT | DRAKKAR LOGISTIC | | | SCAC4 |
| 36 | DKCU | GENERAL CONTAINER SERVICES | | UA | BIC |
| 37 | DKDB | DOUBLE E TRUCKING LTD | | | SCAC4 |
| 38 | DKDG | DAKOTA DRAYAGE & CHASSIS INC | | | SCAC4 |
| 39 | DKDK | DOCK 2 DOCK LLC | | | SCAC4 |
| 40 | DKDM | DESERT KING DE MEXICO S DE R L DE C | | | SCAC4 |
| 41 | DKDR | DIRKES, DAVID TRUCKING | | | SCAC4 |
| 42 | DKDS | DELEK REFINING LTD | | | SCAC4 |
| 43 | DKDT | DKD TRUCKING INC | | | SCAC4 |
| 44 | DKE | Jubilee Airways Ltd. | Callsign: Duke, Name changed from Klinge Aviation Limited. | GB | AVCODES |
| 45 | DKE | Jubilee Airways | | | ICAO1 |
| 46 | DKEC | D & K EXPRESS INC | | | SCAC4 |
| 47 | DKEG | DUKE ENERGY CORPORATION | | | SCAC4 |
| 48 | DKEK | D K EXPRESS | | | SCAC4 |
| 49 | DKEN | DUKE TRANSPORT INC | | | SCAC4 |
| 50 | DKEQ | D & K EXCAVATION LLC | | | SCAC4 |
| 51 | DKER | DIEKER OIL INC | | | SCAC4 |
| 52 | DKFS | DRAKES FUEL SERVICE INC | | | SCAC4 |
| 53 | DKGI | DOMEIKIS, GINTARAS | | | SCAC4 |
| 54 | DKGR | DICKSON GENERAL TRUCKING | | | SCAC4 |
| 55 | DKGT | DEE KING TRUCKING LP | | | SCAC4 |
| 56 | DKGV | DELTA TRUCKING SERVICE | | | SCAC4 |
| 57 | DKH | Juneyao Airlines Co. Ltd. | IATA: HO, Callsign: Air Juneyao, IATA Prefix: 018, | PRC | AVCODES |
| 58 | DKH | Juneyao Airlines | | | ICAO1 |
| 59 | DKIC | DUKES, KELLY INC | | | SCAC4 |
| 60 | DKIL | DANSTOK INT'L | | | SCAC4 |
| 61 | DKIT | DANMA KITCHEN CABINETS LTD | | | SCAC4 |
| 62 | DKLA | DAKOTALAND TRUCK BROKERAGE INC | | | SCAC4 |
| 63 | DKLB | D K LOGISTICS LLC | | | SCAC4 |
| 64 | DKLE | DURDEN TRUCK LINES INC | | | SCAC4 |
| 65 | DKLI | DAKOTA LINES INC | | | SCAC4 |
| 66 | DKLL | D T L | | | SCAC4 |
| 67 | DKLS | DIRCKS LOGISTICS SOLUTIONS | | | SCAC4 |
| 68 | DKLU | ROYAL NETHERLANDS AIR FORCE | | NL | BIC |
| 69 | DKLU | ROYAL NETHERLANDS AIR FORCE DOP/AVV | | | SCAC4 |
| 70 | DKM | Deutsche Kriegsmarine (1919-1945) | | D | TRAFFIC |
| 71 | DKMA | DUKE, MARK | | | SCAC4 |
| 72 | DKME | DECKER, M E TRANSPORT INC | | | SCAC4 |
| 73 | DKMK | D K M TRANSPORTATION INC | | | SCAC4 |
| 74 | DKMV | DUECK MARINE DIVISION | | | SCAC4 |
| 75 | DKMZ | DOTIKI MINE | | | PWRC |
| 76 | DKN | Air Deccan | IATA: DN, Callsign: Deccan, Now Kingfisher Red, known formerly as Simplifly Deccan and prior to that as Air Deccan, is a low-cost airline run by Kingfisher Airlines. Designator DN* reinstated by IATA | IND | AVCODES |
| 77 | DKN | Air Deccan | Callsign: Air Deccan, | IND | AVCODES |
| 78 | DKN | Deccan Aviation | | | ICAO1 |
| 79 | DKNC | DK TRANS INC | | | SCAC4 |
| 80 | DKNK | DICKSON TRUCKING | | | SCAC4 |
| 81 | DKOA | DAKOTA TRANSPORT | | | SCAC4 |
| 82 | DKOC | DARK OIL COMPANY INC | | | SCAC4 |
| 83 | DKOF | DAKOTA OUTLAW FREIGHT INC | | | SCAC4 |
| 84 | DKOS | DORIKOS NAVIGATION CO LTD | | | SCAC4 |
| 85 | DKOU | DAELIM CO., LTD | | ROK | BIC |
| 86 | DKOU | DAELIM H & L CO LTD | | | SCAC4 |
| 87 | DKPS | DESK TOP SERVICES | | | SCAC4 |
| 88 | DKPX | Duke Power Co. LLC d/b/a Duke Energy Carolinas LLC | added 4/2009 | | NAKINA |
| 89 | DKPX | Duke Power Co. (scale test cars) | 1/1994-7/2005 (not listed) | | NAKINA |
| 90 | DKPX | Duke Power Co. (scale test cars) | 1/94-7/2000 | | NRHS |
| 91 | DKPX | DUKE POWER CO. (DUKE ENERGY CAROLINAS, LLC) | | | PWRC |
| 92 | DKPX | Duke Power | | | RSRV |
| 93 | DKPX | DUKE ENERGY CAROLINAS LLC | | | SCAC4 |
| 94 | DKPZ | Doprávný Komunálny Podnik Zilina | | SK | TRAFFIC |
| 95 | DKQC | D & K LOGISTICS LLC | | | SCAC4 |
| 96 | DKQI | DUKAS LOGISTICS INC | | | SCAC4 |
| 97 | DKR | Darik Sky | Callsign: Dima, | BG | AVCODES |
| 98 | DKRB | D & K ROHRER FARMS | | | SCAC4 |
| 99 | DKRI | D K R ENTERPRISES INC | | | SCAC4 |
| 100 | DKS | Union Pacific R.R. Co. | added 4/1997; 7/2000-7/2005 | | NAKINA |
