• Ensure rail safety.
  • Replace outdated infrastructure to make the network more reliable.
  • Upgrade train cars to improve passenger comfort.
  • Provide real-time updates across a range of devices throughout the entire line.
  • Prepare for the future by designing new rolling stock featuring the latest technologies (introducing new, on-board signaling systems; increasing capacity; improving performance; providing greater accessibility; ensuring on-board comfort; quayside interchange time; meeting new standards; etc.) and by adapting infrastructure.


passengers per day


stations on the entire line


trains per day


Réseau Express Régional (RER) Line B is a major transit hub in Ile-de-France. The northern section of the line is operated by SNCF, and the southern section—from Gare du Nord station to both Saint-Rémy-lès-Chevreuse and Robinson—is operated by RATP.

Ridership on RER Line B has grown by 2.5% per year. RER B is the second most widely used line after RER A, and serves two major areas—Service Interacadémique des Examens et Concours (SIEC) and Université Paris-Saclay—and connects Orly and Paris-Charles de Gaulle airports, as well as the TGV railway stations in Massy and at Paris-Charles de Gaulle.

As traffic continues to rise steadily, infrastructure improvements have been planned to increase network reliability and passenger comfort. Upgraded trains feature a more user-friendly layout, air-conditioning and traffic updates in real time. Each train is also equipped with a 24-camera video-surveillance system to ensure passenger safety.

Since 2013, RATP and SNCF Mobilités teams have merged into a single department to ensure operations for RER Line B. This consolidated effort has simplified operation of the line and helped reduce project turnaround time to improve quality of service. Moreover, the Single Command Center (Centre de Commandement Unique - CCU) brings together RATP, SNCF Mobilités and SNCF Réseau to oversee the flow of traffic from north to south in real time, in order to improve quality of service, 24 hours a day, seven days a week.


RER B RATP train Paris
Your future. Our destination.

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Cyril Condé

RER Department Director 

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