The average bus between Trappes and Orsay takes 1h 5m and the fastest bus takes 52 min. There is a bus service every few hours from Trappes to Orsay. The journey time may be longer on weekends and holidays; use the search form on this page to search for a specific travel date.
Buses run hourly between Trappes and Orsay. The earliest departure is at 5:30 AM in the morning, and the last departure from Trappes is at 10:10 PM which arrives into Orsay at 11:15 PM. All services require a transfer, and take on average 1h 5m. The schedules shown below are for the next available departures.

56 min • 1 change

56 min • 1 change

56 min • 1 change

56 min • 1 change

1h 13m • 1 change

1h 11m • 1 change

1h 13m • 1 change

1h 14m • 1 change

52 min • 1 change

53 min • 1 change

56 min • 1 change

1h 6m • 1 change
Want to know about travelling from Trappes to Orsay? We have put together a list of the most frequently asked questions from our users such as: What is the cheapest mode of transport? What is the quickest option? How much do tickets usually cost? and many more.
No, there is no direct bus from Trappes to Orsay. However, there are services departing from Trappes station and arriving at Orsay station via Université Paris-Saclay. The journey, including transfers, takes approximately 1h 5m.
Trappes to Orsay bus services, operated by Lignes Île-de-France Ouest, depart from Lycée Émilie de Breteuil station.
Trappes to Orsay bus services, operated by Lignes Île-de-France Ouest, arrive at Mairie - Hôpital - Orsay RER station.
The distance between Trappes and Orsay is 15.2 km. The road distance is 22 km.
You can take a bus from Lycée Émilie de Breteuil to Mairie - Hôpital - Orsay RER via Université Paris-Saclay in around 58 min.