TER Grand Est, operating under the brand TER Fluo, is the regional rail network serving the region of Grand Est, northeastern France.

It is operated by the French national railway company SNCF on behalf of the region.

The new branding is used to signify TER train services operated in the region.

[1] After a competitive tender process held in 2024, a subsidiary of Transdev was awarded a 22-year concession to operate services on the Nancy to Contrexéville line, scheduled to commence in 2027 after the line (currently closed to traffic) is reopened after refurbishment.

The award marked the end of SNCF’s monopoly on the operation of TER rail services for the Grand Est region.