R9 (RER Vaud)

The R9 is a railway service of RER Vaud that provides hourly service between Lausanne and Kerzers in the Swiss cantons of Vaud and Fribourg, respectively. Swiss Federal Railways, the national railway company of Switzerland, operates the service. The service was previously known as the S9.

Operations
The R9 operates every hour between Lausanne and Kerzers, using the Lausanne–Bern line between Lausanne and Palézieux, and the Palézieux–Lyss line between Palézieux and Kerzers. The R9 runs as an express between Lausanne and Palézieux, stopping only at Puidoux. The R5 and R6 make local stops, combining with the R9 and the InterRegio 15 for service roughly every 15 fifteen minutes. North of Palézieux, the R8 pairs with the R9 for half-hourly service to Payerne. Between Payerne and Kerzers, the Bern S-Bahn S5 runs hourly to Murten/Morat, with limited service to Payerne.

History
RER Vaud introduced the S9 designation with the December 2015 timetable change, replacing the S21. Both routes operated between Lausanne and Payerne. The S9 was extended from Payerne to Kerzers in December 2017.

On 10 December 2023, all RER Vaud lines were renamed as "R" and a number, instead of "S."