RB 23 is the designation of several regional rail services in Germany:

  • RB 23, operated by DB Regio Mitte between Mayen Ost and Limburg (Lahn)
  • RB 23, operated by DB Regio Nordost between BER Airport – Terminal 1-2 and Golm
  • RB 23, operated by DB Regio Nordost between Züssow and Świnoujście Centrum
  • RB 23, operated by DB Regio NRW between Bad Münstereifel and Euskirchen
  • RB 23, operated by Oberpfalzbahn between Regensburg and Marktredwitz or Neustadt (Waldnaab)