From January 1st, 1999, as the SNCF
locomotive inventory is distributed between the different activities, engines may receive a prefix (eventually followed by a "0" if the initial registration number is only 4-digit long) as follows:
: used for long-distance and high-speed rail passenger transport ("Voyages SNCF" / "SNCF Voyages" / "SNCF Voyages France Europe - SNCF VFE");
: used for Intercity trains;
: used for rail freight transport ("Fret SNCF");
: belonging to a region and used for TER ("Train Express Régional") services;
: used for the management and maintenance of the rail infrastructure;
: used for the management and maintenance of rail vehicles (transport of new, under repair or written off railway vehicles);
: belonging to Ile-de-France region and used for TER ("Train Express Régional") services.
It should also be noted that the suffix "R" is used to distinguish units equipped for reversibility.