LEI vs TIN/EIN: What's the Difference?
A TIN or EIN and an LEI are both official numbers attached to an organisation, but they sit at opposite ends of the spectrum: one is a national tax identifier, the other a global market identifier.
What a TIN/EIN is
A TIN (Tax Identification Number) is the general term for the number a tax authority uses to identify a taxpayer. In the United States, the business equivalent is the EIN (Employer Identification Number). These are national identifiers used for tax filing and reporting to the local tax authority. They generally don't travel across borders, and the number itself is often treated as sensitive.
What an LEI is
An LEI (Legal Entity Identifier) is a global, 20-character identifier defined by ISO 17442 and governed by GLEIF, used to identify legal entities in the financial markets. Unlike a tax number, an LEI and its reference data are public — they're meant to be looked up. (See What is an LEI code?)
The contrast
- Purpose: TIN/EIN = taxation; LEI = financial-market identity.
- Scope: TIN/EIN = national; LEI = global.
- Privacy: TIN/EIN is typically private and sensitive; LEI is public by design.
A business in the financial markets holds both, but should never use one in place of the other.
See also LEI vs VAT number and LEI vs DUNS number.