Overview
ISO 3780:2009 defines the World Manufacturer Identifier (WMI) - the three-character code that forms the first section of the vehicle identification number (VIN) specified in ISO 3779. The standard specifies the content, format and assignment rules for WMI codes to ensure unique, worldwide identification of road vehicle manufacturers. It applies to motor vehicles, towed vehicles, motorcycles and mopeds as defined in ISO 3833.
Key topics and requirements
- WMI structure: A WMI is exactly three characters (letters and digits). The WMI is the first section of the VIN and, when combined with the rest of the VIN, helps guarantee global uniqueness for at least 30 years.
- Allowed characters: Only digits 0–9 and uppercase letters A–Z are used, excluding I, O and Q to avoid confusion.
- Character roles:
- First character identifies a geographic region.
- Second character, together with the first, identifies a specific country within that region (distribution given in Annex A).
- Third character is assigned by the national authority to identify a specific manufacturer. Multiple WMIs may be assigned to one manufacturer when needed.
- Small-volume manufacturers: National bodies should use the digit 9 as the third character for manufacturers producing fewer than 500 vehicles per year; in this case some VIS positions are allocated by the national body to ensure identification.
- Allocation and administration: National bodies assign WMIs for manufacturers headquartered in their country. The SAE acts as the international maintenance agency for the WMI matrix (Annex A), and allocation must be controlled internationally.
- Reuse restriction: A WMI must not be reassigned to a different manufacturer for at least 30 years after its last year of use.
Applications
- Vehicle manufacturers and assemblers use ISO 3780:2009 to obtain and apply a WMI for VIN marking and manufacturer identification.
- National registration authorities, type-approval agencies, customs, law enforcement and vehicle import/export authorities rely on WMIs to identify origin and manufacturer.
- VIN issuers, compliance officers, fleet managers and vehicle history services use the WMI to validate manufacturer identity and support traceability, recalls and anti-fraud processes.
Related standards
- ISO 3779 - VIN content and structure (WMI is the VIN’s first section)
- ISO 3833 - Vehicle type definitions referenced for scoping
- SAE resources and NHTSA VIN/WMI listings provide practical guidance and current WMI allocations.
Keywords: ISO 3780:2009, World Manufacturer Identifier, WMI, VIN, vehicle identification number, manufacturer codes, SAE, ISO 3779, ISO 3833.
