EUID
EUID is the European Unique Identifier that every company and branch registered in an EU member state carries, so that business registers across the Union can refer to the same entity without ambiguity. It is structured to ISO 6523 and combines a country code, an identifier for the register of origin, the registration number in that register and an optional verification digit.
Company data sits in national registers that each number their companies in their own way. Article 16(1) of Directive (EU) 2017/1132 therefore requires Member States to ensure that companies have a unique identifier that allows them to be unequivocally identified in communications between registers, through the system of interconnection of registers known as BRIS. The EUID is that identifier, and it is carried by companies and by their branches.
Implementing Regulation (EU) 2021/1042 sets out how it is built. The structure of the EUID is compliant with ISO 6523 and contains four elements: a country code, a register identifier and the registration number, which are mandatory, and a verification digit, which is optional. The register identifier names the domestic register of origin and the registration number is the one the company holds in that register, so an EUID is built from a number the company already has.
In the European Business Wallet the EUID is what ties a wallet to a legal entity. The WE BUILD architecture blueprint describes an EBWOID as a stable, minimal set of identity attributes, primarily the official company name and its EUID, and WE BUILD uses the EUID, with national registration codes for operators that BRIS does not cover, as the identifier an EBWOID is built on. The European Business Wallet proposal, COM(2025) 838, would likewise designate the EUID as the unique identifier of a wallet owner, but it is still a proposal and its text can change.
- Directive (EU) 2017/1132, Article 16(1)
- Implementing Regulation (EU) 2021/1042, Annex, section 9
- WE BUILD terminology, concept webuild:concept-110
- WE BUILD D4.1 Architecture & Integration Blueprint
Related terms
Is an EUID the same as a company registration number?
No. The registration number is only one part of it. A national registration number has meaning in one register only, and the same number can occur in more than one register. The EUID adds a country code and a register identifier in front of it, which makes the number unambiguous across all the registers that exchange data through BRIS.
The EUID is also not the same as an LEI. An LEI is a global 20-character code under ISO 17442, issued by accredited Local Operating Units, while an EUID is built from the registration number a company holds in its own EU register.