One-stop shop (OSS)

The one-stop shop is ERA's single application portal for the EU-level authorisations created by the Fourth Railway Package: vehicle (type) authorisations, single safety certificates, and ERTMS trackside approvals. Instead of applying separately in each member state, an applicant files once through the OSS; ERA acts as the authorising entity when the area of use covers more than one member state (the national safety authority can still handle single-state cases), coordinating the assessment with the NSAs concerned. The applicant chooses the authorising entity for single-state cases — one of the package's practical flexibility points. The OSS is also where pre-engagement happens: applicants can ask for a view on their approach before formally applying, which for complex first-of-class projects is often the difference between a smooth file and a contested one. Regulation (EU) 2018/545 details the vehicle-authorisation process stages and decision timelines; Regulation (EU) 2018/763 does the same for safety certificates.