What is the Stammnummer and how is it structured?
Last verified: 2026-06-20
The Stammnummer is the vehicle-related identifier assigned by the authorities in the Vehicle Admission Information System (IVZ). It must be distinguished from the manufacturer-stamped chassis number (VIN): the Stammnummer is assigned by Swiss authorities — by the Federal Office for Customs and Border Security (BAZG) at customs clearance or by a cantonal road traffic office.
The Stammnummer assigned by the BAZG has 9 digits. The first digit encodes the origin:
- First digit 1–8: customs Stammnummer, assigned by the BAZG after customs clearance.
- First digit 9: cantonal Stammnummer, assigned by a cantonal road traffic office (format 9xx.xxx.xxx).
In the IVZ the Stammnummer is the link between licence plate, type data and keeper. Vehicle data can be retrieved via the electronic data sheet portal using the Stammnummer. In its open data products ASTRA publishes Stammnummern in pseudonymised form.
Assignment of the Stammnummer (BAZG, Annex VI WPB 13.20): version in force (As of: 2024-01-01)
Sources
- Annex VI: BAZG – assignment of the Stammnummer after checking customs clearance — ASTRA / BAZG
- FAQ – Vehicle data information products — ASTRA – Federal Roads Office
- Electronic data sheet portal (eDatenblatt) — ASTRA – Federal Roads Office