RER A works: dates, times, and alternatives between October and November 2026 Last updated: October 1, 2026
Between October and November 2026, the RER A line will be closed on certain dates and on several sections. These closures have a direct impact on your journeys: find the schedule and our advice in this article.
Key dates
Service interruptions are scheduled on the RER line 
to modernize infrastructure, strengthen safety, and improve passenger comfort.
Alternative transport options will be provided during these periods.
🚫 Interruption Nanterre–Préfecture <> Cergy–Le Haut/Poissy from 10:00 p.m.
- From Thursday October 1 to Friday October 9 inclusive, Monday to Friday
- From Monday November 9 to Friday November 13 inclusive
- On Monday November 30
Alternative route: - Nanterre–Université <> Cergy–Le Haut (all stops and semi-fast)
- Nanterre–Université <> Poissy (all stops)
- Achères Grand Cormier <> Sartrouville / Maisons-Laffitte / Poissy (on-demand transport)
🚫 Interruption Maisons-Laffitte <> Cergy-Le Haut from 9:50 p.m.
- From Monday October 12 to Friday November 27 inclusive, Monday to Friday (except the week from Monday November 9 to Friday November 13)
Alternative route: - Sartrouville <> Cergy-Le Haut (all stops and semi-fast)
🚫 Interruption La Varenne-Chennevières <> Boissy-Saint-Léger from 9:45 p.m.
- From Monday October 12 to Thursday October 29 inclusive
Alternative route: - La Varenne-Chennevières <> Boissy-Saint-Léger (all stops)
Adapt your journeys with the Bonjour RATP app
🔎 Find the best route
Start a route search: the results anticipate disruptions to help you avoid work areas. Then customize according to your needs: schedules, transport modes, lines or stations to avoid…
🚦 Check live traffic updates
Access real-time traffic status via the app's Traffic tab. You can enable personalized alerts to be notified when your lines are affected.
📹 Demo: follow traffic updates with the app
Viewing this video is subject to your consent regarding the use of cookies and data sharing with our partners. Please accept the terms to access the content.
The Bonjour RATP app, your ally for anticipating disruptions and
finding the best routes during works
These articles might interest you
From now on, you can help boost the visibility of Bonjour RATP articles in Google News.How does it work?Choose as preferred source
