
Île-de-France Mobilités is launching a new numbering of bus lines and a restructured offer in the Île-de-France Ouest region.
We explain everything to you!
Why does the number of the lines change?
The Ile-de-France bus network is made up of about 1,900 lines, with numbering systems that coexist, but are not alike.
Currently, there are very differentnames (1, TEx, 340, 95-02, 11L...) and duplicates in line numbers (there are 19 lines 2 on the current bus network), which complicates the understanding of the network.
How to find your way around the new issues?
Île-de-France has been divided into departments and sectors, each with a specific code, according to where the line is running.
Île-de-France has been divided into departments and sectors, each of which has a specific code.
- The lines serving the territory of Saint-Quentin-en-Yvelines start with the number of the sector concerned, i.e. 51 (lines 5116, 5117, 5154...).
- Following the same logic, line 5234, which serves the Centre and South Yvelines territory, begins with 52, the number of the territory attached to it.
- Finally, the numbers of the Express lines start with the number of their department (7802, 7804, 9111...).
What will this new number bring to passengers?
Passengers will be able to find their bus line more easily when searching on the app or the iledefrance-mobilites.fr website, as it will be the only one in Île-de-France to have this number.

An adapted and reinforced line offer
Line 7804 (ex express line 4)
- 1 more trip in the afternoon (around 4:30 p.m.) in both directions
Line 7802 (ex express line 27)
- Modification of the route and service of new stops (Pont Rive Droite / Conflans Fin d'Oise, Pontoise station)
Line 7808 (ex express line 80)
- Cancellation of trips to and from Libération
- 4 additional departures on weekdays and 2 on Saturdays
- Extension of the offer until 10 p.m. in both directions from Monday to Saturday
Line 5116 (ex line 501)
- The 6:55 a.m. departure from Saint-Quentin-en-Yvelines station is extended to Mantes (instead of Epône currently)
Line 7803 (ex line 503)
- A new terminus in Nanterre Préfecture
- Modification of the route to connect the poles of Saint-Quentin-en-Yvelines and Nanterre Préfecture
- 5 additional trips each way
- First departures earlier in the morning (from 5:55 am) and later in the evening (until 7:35 pm)
Line 9111 (ex express line 91-11)
- The range of services extended in the evening until 10:30 p.m. from Saint-Quentin-en-Yvelines and 10:20 p.m. from Massy.
Line 7807 (ex express line 307): new, more direct route of the line
- Modification of the technocentre service
- Thinner service to Vélizy
- Cancellation of services to the Chantiers and Buc stations (possible transfer to lines 5150, 6161 and 6164)
- Removal of the Petit Robinson antenna
Line 7815 (ex line 15)
- Modification of the route of the line with the service of new stops: Jacques Monod and Les Grands Jardins in Plaisir
- 8 more trips on the line between Plaisir and Saint-Cloud: 4 in the morning from 7:05 am to 8:35 am and 4 in the evening between 5:05 pm and 6:45 pm
Line 5153 (ex line 39-34)
- Extended amplitude of the line, which now operates from 5:58 a.m. to 7:45 p.m.
- 6 additional departures: 3 in the morning from Guyancourt and 3 in the evening from Boulogne
Lines whose offer remains unchanged
- Line 7816 (ex express line 16)
- Line 7818 (ex express line 78)
- Line 5154 (ex express line 91-10)
- Line 5117 (ex line 17)
- Line 7805 (ex line 475)
- Line 5146 (ex line 39-12)
- Line 5234 (ex line 78S)
To find the information of all your lines:
Website: iledefrance-mobilites.fr
- To calculate a trip: me-deplacer.iledefrance-mobilites.fr/itineraire
- To find the timetables: Lines Île-de-France Ouest
- To follow local news (only on the website): Île-de-France Ouest news page