| 1 | UDIET | Gleis- und Signalbau Uwe Dietrich | | DE | VKM |
| 2 | UDIP | UNITED DISPATCH INC | | | SCAC4 |
| 3 | UDIQ | URQUART DELIVERY INC | | | SCAC4 |
| 4 | UDIX | Utilities Distributors, Inc. | 1/1943 | | NAKINA |
| 5 | UDIX | Utilities Transport Co. | 1/1945 | | NAKINA |
| 6 | UDIX | Utilities Distributors Gas Co., Inc. | 1/1946-1/1950 | | NAKINA |
| 7 | UDIX | Utilities Distributors, Inc. | 1/1952; eliminated 7/1953 | | NAKINA |
| 8 | UDIX | Utilities Distributors, Inc. | Jan-52 | | NRHS |
| 9 | UDIX | UTILITIES DISTRIBUTORS, INC. [UTILITIES TRANSPORT CO.] | | | PWRC |
