RER Jura () is an S-Bahn network in the canton of Jura in Switzerland. It is centered on Porrentruy and began operating in December 2025.
As of December 2025 the network consists of the following lines:
The RER Jura network began operation on 14 December 2025. Between Delémont and Porrentruy, the new R1 and R2 combine for half-hourly service, with hourly service to Delle (France) and Bonfol. This replaced a mix of Basel S-Bahn (S3), RegioExpress (RE56) and Regio (R51) services. The R11 and R22 provide hourly service from Porrentruy to Delle and Bonfol, respectively. Services operate over the DelémontâÂÂDelle railway line of Swiss Federal Railways (SBB CFF FFS) and the PorrentruyâÂÂBonfol railway line of Chemins de fer du Jura (CJ).