| 1 | GLA | Great Lakes Aviation Ltd. | IATA: ZK, Callsign: Lakes Air, IATA Prefix: 846, Ceased operations on 26 March 2018. | USA | AVCODES |
| 2 | GLA | Great Lakes Airlines | IATA: ZK | | ICAO1 |
| 3 | GLA | Great Lakse Airlines | | USA | TRAFFIC |
| 4 | GLAB | GLABS TRUCKING | | | SCAC4 |
| 5 | GLAD | GLAD LOGISTICS INC | | | SCAC4 |
| 6 | GLAF | G L J FISHING CO LTD | | | SCAC4 |
| 7 | GLAH | GLADWIN FARMS LTD | | | SCAC4 |
| 8 | GLAI | GREAT LAKES AND INTERNATIONAL TOWIN | | | SCAC4 |
| 9 | GLAL | GLOBAL ALLIANCE LOGISTICS INC | | | SCAC4 |
| 10 | GLAO | GRAEBEL/LOS ANGELES MOVERS INC | | | SCAC4 |
| 11 | GLAS | | City: Glasgow | GB | TRAFFIC |
| 12 | GLASC | Glasgow Corporation | | GB | TRAFFIC |
| 13 | GLAU | GASPRO LATINOAMERICA S.A | | PA | BIC |
| 14 | GLAU | AVV. DOTT. SERGIO GUGLIELMETTI | | | SCAC3 |
| 15 | GLAZ | GREAT LAKES INDUSTRIES | | | PWRC |
