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.

J

• JAIL - Jackson and Lansing Railroad
• JAAU - Jordan Bromine Company
• JACX - Johnstown America Corporation
• JAIX - JAIX Leasing Corporation
• JALX - JAIX Leasing Corporation
• JANX - JAN, Inc.
• JBHU - J.B. Hunt Transport, Inc.
• JBHZ - J.B. Hunt Transport, Inc.
• JBIX - Tank Car Services, Inc.
• JBPX - PacifiCorp Electric Operations and Idaho Power Company (Jim Bridger Project)
• JBRX - Bakery Trading Company
• JBTU - Jumbotainer BV Barendecht
• JCDX - Jefferson County Drainage District No. 6
• JCEX - John S. Carlson and Company, Inc.
• JCIX - Jones Chemicals, Inc.
• JCLX - Mid-Am Equipment, Inc.
• JCMX - James C. McCanless
• JCSX - Sawyer Gas of Jacksonville, Inc., Heritage Operating, LP
• JDHX - J.D. Heiskell & Co, LLC
• JDIX - Jim Dobbas, Inc.
• JDMX - The David J. Joseph Co.
• JDSX - M and C Railcar Leasing, LLC
• JE - Jerseyville and Eastern, Joppa and Eastern Railroad
• JECX - Western Resources, Inc.
• JEFW - Jefferson Warrior Railroad
• JEPX - PSI Energy, Inc.
• JFDX - W. K. Horney
• JGLU - Juglinija Lines
• JGRU - John G. Russell Transport, Ltd.
• JGS - James Griffiths and Sons
• JHMX - Alabama Power Company
• JHPX - Huntsman Chemical Corporation, NOVA Chemicals
• JJJX - JJ Railcar Leasing, Ltd.
• JJRD - J and J Railroad
• JKBX - John Kenneth Burbridge
• JKL - J.K. Line, Inc.
• JKWI - Johnsonburg, Kane, Warren and Irvine Railroad
• JLAU - Japan Line, Ltd.
• JLDU - Japan Line, Ltd.
• JLEU - Japan Line, Ltd.
• JLEZ - Japan Line, Ltd.
• JLHU - Japan Line, Ltd.
• JLLU - Japan Line, Ltd.
• JLLX - LaRoche Industries, Inc.
• JLLZ - Japan Line, Ltd.
• JLMU - Japan Line, Ltd.
• JLMX - John L. McCarthy
• JLPU - Japan Line, Ltd.
• JLSU - Japan Line, Ltd.
• JLSZ - Japan Line, Ltd.
• JLTU - Japan Line, Ltd.
• JMHX - J. M. Huber Corporation
• JMJZ - J.M.J. Projects, Inc.
• JNSX - JNS Marketing Company (Coastline Rail Service Division)
• JNTX - John Neas Tank Lines
• JOBX - Tealinc, Ltd.
• JORX - Jormac, SA de CV
• JOSX - The David J. Joseph Co.
• JOTU - Japan Oil Transportation Company, Ltd.
• JPBX - Peninsula Corridor Joint Powers Board (Caltrain)
• JPTU - Daikin Industries
• JPWX - Junior Police Works, Inc
• JRCX - GLNX Corporation
• JRSX - J. R. Simplot Company
• JRTX - Jefferson Energy Companies
• JRWX - Johnson Railway Service, Inc.
• JSCU - Flexi-Van Leasing, Inc.
• JSCZ - Flexi-Van Leasing, Inc.
• JSRC - Jackson and Southern Railroad
• JSRW - Jersey Southern Railway
• JSSU - China Navigation Company, Ltd.
• JSSX - Jersey Shore Steel Company
• JTAX - Trinity Rail Management, Inc.
• JTCO - Jacksonville Terminal Company
• JTFX - Joseph Leasing, Ltd.
• JTHX - Thomas D. Hicks, Citicorp Railmark, Inc.
• JTIX - The David J. Joseph Co.
• JTJX - The David J. Joseph Co.
• JTLX - The David J. Joseph Co.; CIT Group/Capital Finance, Inc.
• JTMX - ISG Resources, Inc.
• JTPX - The David J. Joseph Co.
• JTSX - The David J. Joseph Co.
• JTSZ - Jontri Transportation Company
• JTTX - TTX Company
• JUGU - Jogolinja
• JVRR - Juniata Valley Railroad
• JWAX - GE Rail Services Corporation
• JWFX - J. W. Flammer Company, Inc.
• JWRX - Jim Walter Resources, Inc., Alabama Power Company