| Abbreviation | Definition |
|---|---|
| KRIX | General Electric Railcar Services Corporation |
| KRIX | Kyle Railways (GE Rail Services Corporation) |
| KRL | Kasgro Rail Lines |
| KRPX | Associated Electric Cooperative |
| KRR | Kiamichi Railroad |
| KRR | Kiamichi Railroad Company, L. L. P. |
| KRSX | Kurguz Railway Services |
| KSCU | Korea Shipping Corporation |
| KSCZ | Korea Shipping Corporation |
| KSMX | Kosmos Cement |
| KSR | Kalka Shimla Railways |
| KSRY | Kosciusko and Southwestern Railway |
| KSW | Kansas and Oklahoma Railroad |
| KSW | Kansas Southwestern Railway |
| KT | Kentucky and Tennessee Railway |
| KT | Kentucky and Tennessee Railway Company |
| KTR | Kendallville Terminal Railway |
| KTTX | Trailer Train (TTX Corporation) |
| KTTX | TTX Company |
| KTX | ACF Industries Incorporated |