| 1 | BK | Potomac Air, Inc. | ICAO: PDC, Callsign: District, IATA Prefix: 522, Formed out of merger of United Air Lines and US Airways | USA | AVCODES |
| 2 | BK | Paradise Island Airlines, Inc. d/b/a Paradise Airlines | Name changed from Paradise Island Airlines, Inc. | USA | AVCODES |
| 3 | BK | Transpolar A/S | Callsign: Trapo, | N | AVCODES |
| 4 | BK | Israel Aircraft Industries Ltd. | ICAO: IAI, Callsign: Bravo Kilo, Designator BK recalled by IATA. ICAO callsign changed to Israel Aircraft | IL | AVCODES |
| 5 | BK | Okay Airways Company Limited | ICAO: OKA, Callsign: Okayjet, IATA Prefix: 866, Designator BK* reinstated by IATA | PRC | AVCODES |
| 6 | BK | Borkumer Kleinbahn und Dampfschifffahrt GmbH | Borkum | D | privat-bahn.de |
| 7 | BK | SHOWA LINE, LTD. | | | PWRC |
| 8 | BK | BK Tåg AB | 1989 - 2005 | S | svenska-lok.se |
| 9 | BK | BK Tåg AB | 1989 - 2005 | S | TRAFFIC |
| 10 | BKA | Bankair, Inc. | IATA: B4, Callsign: Bankair, Designator B4* recalled by IATA | USA | AVCODES |
| 11 | BKA | Bankair, Inc. | Callsign: Bankair, Designator B4* recalled by IATA | USA | AVCODES |
| 12 | BKA | Bankair | IATA: B4 | | ICAO1 |
| 13 | BKAB | BARKER, ALBERT | | | SCAC3 |
| 14 | BKAC | BEKA TRANSPORT CORP | | | SCAC3 |
| 15 | BKAC | BREAKAWA | | | SCAC4 |
| 16 | BKAD | BLACK KNIGHT TRUCKING INC | | | SCAC4 |
| 17 | BKAE | BOOKERS AIR CARGO EXPRESS | | | SCAC3 |
| 18 | BKAE | BANNER DOORS CORP OF NEW YORK | | | SCAC4 |
| 19 | BKAF | BANKS, GEORGE TRUCKING | | | SCAC4 |
| 20 | BKAI | BANKAIR INC | | | SCAC3 |
| 21 | BKAI | BAKER, AL & SON TRUCKING INC | | | SCAC4 |
| 22 | BKAK | BLAKE AGRI TRANSFER INC | | | SCAC4 |
| 23 | BKAL | BERKELEY ASPHALT CO | | | SCAC3 |
| 24 | BKAL | BUSH TRUCKING LLC | | | SCAC4 |
| 25 | BKAM | BULKAMERICA CORP. | | | SCAC3 |
| 26 | BKAN | B K & N INC | | | SCAC3 |
| 27 | BKAN | BRICKER TRANSPORT | | | SCAC4 |
| 28 | BKAP | BREMERTON KITSAP AIRPORTER INC | | | SCAC3 |
| 29 | BKAQ | BLAKE, THOMAS TRUCKING | | | SCAC4 |
| 30 | BKAR | BROCKTON AREA TRANSIT AUTHORITY | | | SCAC3 |
| 31 | BKAR | BINGHAMTON TRUCK & TIRE CENTER LLC | | | SCAC4 |
| 32 | BKAS | BUCKEYE AIR SERVICE INC | | | SCAC3 |
| 33 | BKAT | BROOKS FURNITURE XPRESS INC | | | SCAC4 |
| 34 | BKAW | BREAKAWAY | | | SCAC3 |
| 35 | BKB | State Of West Virginia, Aviation Division | Callsign: Black Bear, | USA | AVCODES |
| 36 | BKBC | BLACKBURN CARTAGE INC | | | SCAC3 |
| 37 | BKBC | BANKS BROKERAGE CO INC | | | SCAC4 |
| 38 | BKBE | BUCKBOARD EXPRESS | | | SCAC3 |
| 39 | BKBG | BKB TRUCKING LLC | | | SCAC4 |
| 40 | BKBI | BLACKBURNS TRANSFER & STORAGE INC | | | SCAC3 |
| 41 | BKBJ | BACK-TO-BACK TRUCKING LLC | | | SCAC4 |
| 42 | BKBK | BAKER & BAKER TRUCKING INC | | | SCAC3 |
| 43 | BKBK | BAKER, PETER E ANTIQUES | | | SCAC4 |
| 44 | BKBL | BONNY-KAY BUS LINES INC | | | SCAC3 |
| 45 | BKBL | BACK IN BLACK INC | | | SCAC4 |
| 46 | BKBN | BANNOCKBURN EXPRESS INC | | | SCAC4 |
| 47 | BKBO | BAKER BROTHERS TRUCKING COMPANY | | | SCAC3 |
| 48 | BKBP | BLACKBURN OIL COMPANY LLC | | | SCAC4 |
| 49 | BKBQ | BROCKHOUSE BROTHERS CORP | | | SCAC3 |
| 50 | BKBR | BAKER BROTHERS TRUCKING | | | SCAC3 |
| 51 | BKBS | BRAKEBUSH TRANSPORTATION INC | | | SCAC3 |
| 52 | BKBS | BRAKEBUS | | | SCAC4 |
| 53 | BKBT | BLACKSBURG TRANSFER & STORAGE INC | | | SCAC3 |
| 54 | BKBT | BECK BULK TRANSPORT LLC | | | SCAC4 |
| 55 | BKBU | L&T C.V. | | NL | BIC |
| 56 | BKBU | BROEKEMA BULK BV | | | SCAC4 |
| 57 | BKBV | BANNOCKBURN SERVICES INC | | | SCAC4 |
| 58 | BKBY | BARK BOYS INC | | | SCAC3 |
| 59 | BKCA | BANKSTON, C A TRUCKING CO | | | SCAC3 |
| 60 | BKCB | BERKSHIRE CABULANCE INC | | | SCAC3 |
| 61 | BKCC | BULK CARRIER SERVICES INC | | | SCAC4 |
| 62 | BKCD | BUCKBOARD CARRIERS INC | | | SCAC3 |
| 63 | BKCD | BULK OR LIQUID TRANSPORT LLC | | | SCAC4 |
| 64 | BKCE | BRAKE, CHARLES E CO INC | | | SCAC3 |
| 65 | BKCF | BEKINS CENTURY FORWARDING INC | | | SCAC3 |
| 66 | BKCG | BRICK CARTAGE COMPNY | | | SCAC3 |
| 67 | BKCG | BLUE STREAK COURIER SERVICE INC | | | SCAC4 |
| 68 | BKCH | BAKER, CHARLES H JR-BUSINESS TRUST | | | SCAC3 |
| 69 | BKCI | BAKICH, E A TRUCKING INC | | | SCAC3 |
| 70 | BKCK | BROCK TRUCKING INC | | | SCAC4 |
| 71 | BKCL | BROKEN CIRCLE TRANSPORTATION INC | | | SCAC3 |
| 72 | BKCM | BULK COMMODITIES TRANSPORT INC | | | SCAC3 |
| 73 | BKCM | BECKETTS CREEK FARMS | | | SCAC4 |
| 74 | BKCN | B K TRUCKLINES INC | | | SCAC4 |
| 75 | BKCO | BERKS MUTUAL LEASING CORP | | | SCAC3 |
| 76 | BKCO | BK TRUCKING COMPANY INC | | | SCAC4 |
| 77 | BKCP | BLOCKSOM & COMPANY | | | SCAC3 |
| 78 | BKCP | BLUESKY CORPORATION | | | SCAC4 |
| 79 | BKCQ | BURKE CARTAGE | | | SCAC3 |
| 80 | BKCR | BROOKS CONTRACT CARRIERS INC | | | SCAC3 |
| 81 | BKCR | BROOKSIDE COLD STORAGE INC | | | SCAC4 |
| 82 | BKCS | B O T TRUCKING CO | | | SCAC3 |
| 83 | BKCT | BUCK COMPANY, THE | | | SCAC3 |
| 84 | BKCT | BUCK COMPANY, THE | | | SCAC4 |
| 85 | BKCV | B K C INC | | | SCAC3 |
| 86 | BKCV | BROOKS COURIER SERVICE INC | | | SCAC4 |
| 87 | BKCX | The Berkshire Chemical Co. | 7/1935-4/1938 | | NAKINA |
| 88 | BKCX | The Berkshire Chemical Co. | Apr-38 | | NRHS |
| 89 | BKCX | BERKSHIRE CHEMICAL CO. | | | PWRC |
| 90 | BKCY | BLOCKHOUSE CO INC | | | SCAC3 |
| 91 | BKCY | BLOCKHOUSE CO INC | | | SCAC4 |
| 92 | BKD | Borkumer Kleinbahn und Dampfschifffahrt | | DE | VKM |
| 93 | BKDA | BROCK, DARRELL | | | SCAC3 |
| 94 | BKDB | BICKFORD, ROBERT LEE | | | SCAC4 |
| 95 | BKDC | BEKINS DISTRIBUTION CENTER | | | SCAC3 |
| 96 | BKDD | BAKER, DALE C | | | SCAC3 |
| 97 | BKDD | BECKER, D D | | | SCAC4 |
| 98 | BKDE | BLACK DIAMOND TRANSPORTATION INC | | | SCAC3 |
| 99 | BKDE | BUICK DESIGNS | | | SCAC4 |
| 100 | BKDG | BECKER, DEAN GORDON | | | SCAC3 |
