Note: Marks ending in U are for container owners; marks ending in X are not common carriers; marks ending in Z are for trailers without flanged wheels. All other marks are of common-carrier railroads.

K

• KABX - Kaber Company, Canadian Resource Distribution, Inc.
• KACX - Kaiser Aluminum and Chemical Corporation
• KAIX - Rinker Materials Corporation
• KAMX - Kamen, Inc.
• KARX - Hamilton Elevators
• KBSR - Kankakee, Beaverville and Southern Railroad
• KBSZ - Kankakee, Beaverville and Southern Railroad
• KCCX - Kennecott Utah Copper Corporation
• KCDX - Eastman Kodak Company
• KCGX - Kaiser Cement Corporation, Southdown, Inc.
• KCIX - ARCO Chemical Company, Nova Chemicals, Inc.
• KCLX - Kansas City Power and Light Company
• KCMO - Kansas City, Mexico & Orient
• KCMX - Kidd Creek Mines, Ltd.
• KCNW - Kelley's Creek and Northwestern Railroad
• KCPX - Kemira Chemicals Canada, Inc.
• KCR - Keewatin Railway Company
• KCRX - Kootenay Central Rail Services, Ltd.
• KCS - Kansas City Southern Railway
• KCSM - Kansas City Southern de Mexico
• KCSU - Kansas City Southern Railway
• KCSZ - Kansas City Southern Railway
• KCT - Kansas City Terminal Railway
• KCTV - KCT Railway
• KCWB - Kansas City Westport Belt
• KCWX - Kimberly-Clark of Canada, Ltd.
• KDCX - Eastman Chemical Canada, Inc.
• KDEX - GLNX Corporation
• KE - Kansas Eastern Railroad
• KEBX - Ronald L. Boothman Remainder Trust
• KELX - Kellogg Company
• KENN - Kennecott Company Railroad
• KENX - KENX Associates
• KET - Kennewick Terminal Railway
• KEWH - Kewash Railroad
• KEYX - Keywell Corporation
• KFGX - Knauf Fiber Glass, GmbH
• KFMX - Oils Unlimited
• KFPX - Koppers Company, Inc.
• KFR - Kettle Falls International Railway
• KFTX - J and J Railcar Leasing, LLC
• KGCX - Koppers Company, Inc., INDSPEC Chemical Corporation
• KGFX - Kingsford Company
• KGLX - Commonwealth Edison Company
• KGRX - Kasgro Rail Corporation
• KIIX - Koppers Industries, Inc.
• KJR - Kiski Junction Railroad
• KJRY - Keokuk Junction Railway
• KKLU - K Line
• KKLZ - K Line
• KKRR - Knox and Kane Railroad
• KKRX - Kaskaskia Regional Port District Railroad
• KKTU - Kerr Steamship K Line
• KLCU - IBJ Leasing Company, Ltd.
• KLL - Klickitat Log and Lumber, J. Neils, St. Regis Paper Co.
• KLSC - Kalamazoo, Lake Shore and Chicago Railway
• KLSX - Kerford Limestone Company
• KM - Kansas and Missouri Railway and Terminal Company
• KMCU - Mitsui O.S.K. Lines, Ltd.
• KMCX - Kerr-Mcgee Coal Corporation
• KMEU - K Line
• KMFX - Kaolin Mushroom Farms, Inc.
• KMLX - Kodiak Mining
• KMTU - Hyundai Merchant Marine (America), Inc.
• KMTX - Kinder Morgan, Inc.
• KMTZ - Hyundai Merchant Marine (America), Inc.
• KMUX - Kershaw Manufacturing Company
• KNC - Kingcome Navigation
• KNDX - Golden State Metals, Inc., KND Rail Services, Inc.
• KNLU - Nedlloyd Lines
• KNOR - Klamath Northern Railway
• KNOX - Philips Metals, Inc.
• KNWA - Kanawha River Railroad
• KO - Kansas and Oklahoma Railroad
• KOAX - Coca-Cola USA a division of the Coca-Cola Company
• KOG - Kansas, Oklahoma and Gulf Railway; Missouri Pacific Railroad; Union Pacific Railroad
• KPCX - Koppers Company, Inc., Koppers Industries, Inc.
• KPCZ - K and P Cartage Company
• KPGX - Kentucky Processing Company
• KPLU - K Line
• KPLX - Koppel, Inc., Western Resources, Inc.
• KPPX - KRATON Polymers US, LLC
• KPR - Kelowna Pacific Railway, Ltd.
• KPRR - Kodak Park Railroad
• KPRX - Kauai Plantation Railway
• KPXX - Progress Rail Services Corporation
• KRDX - KRDX Company
• KRIX - GE Rail Services Corporation
• KRL - Kasgro Rail Lines
• KRPX - Associated Electric Cooperative, Inc.
• KRR - Kiamichi Railroad
• KRSX - Kurguz Enterprises, Inc. (Kurguz Railway Services)
• KRXX - Knife River Corp.
• KRT - Kanawha River Terminal
• KSCU - Korea Shipping Corporation
• KSCZ - Korea Shipping Corporation
• KSMX - Kosmos Cement Company, Inc.
• KSPX - K+S Potash Canada GP
• KSRY - Kosciusko and Southwestern Railway
• KSW - Kansas and Oklahoma Railroad
• KT - Kentucky and Tennessee Railway
• KTR - Kendallville Terminal Railway
• KTTX - Trailer Train Company, TTX Company
• KTX - ACF Industries, Inc.
• KUCX - Kentucky Utilities Company
• KVR - Kern Valley Railroad
• KV&W - Kansas City, Kaw Valley and Western Railway
• KWCU - World Container Leasing, Inc.
• KWT - K.W.T. Railway
• KWTR - Keota Washington Transportation Company
• KWUX - Utility Power Corporation, Siemens Westinghouse Power Corporation
• KXHR - Knoxville and Holston River Railroad
• KYLE - Kyle Railroad
• KYLU - NYK Line
• KYRX - Progress Rail Services Corporation