What Is an IBAN?

The IBAN, which stands for International Bank Account Number, is the basic identity of the euro and many international payments. For most SEPA transfers, the IBAN alone is enough. In this guide we explain what an IBAN is, which parts it consists of, and how it works.

The structure of an IBAN

An IBAN consists of three main parts:

• Country code (2 letters): The ISO 3166 country code — for example, DE (Germany), FR (France), TR (Turkey).
• Check number (2 digits): The MOD-97 (ISO 7064) checksum; it catches typing errors.
• BBAN (country-specific): Country-specific information such as the bank code and account number.

IBAN length varies by country: Germany 22, France 27, the Netherlands 18, Turkey 26 characters. Each country's IBAN length is fixed; this is one of the first checks used in validation.

How does the MOD-97 checksum work?

The IBAN's greatest strength is the MOD-97 check mechanism it contains. The first four characters are moved to the end, the letters are converted into numbers, and the remainder of dividing the resulting large number by 97 must be 1. In this way, when a single digit or letter is entered incorrectly, the IBAN is most likely flagged as invalid. If you want to run this check on your own IBAN, you can use the IBAN validation tool.

An important limit: valid ≠ active

An IBAN being mathematically valid does not prove that the account actually exists or is active. It is possible to send money to a wrong but structurally valid IBAN; that is why you should always confirm the recipient's details. For services that check the payee name–IBAN match, see the payee name–IBAN mismatch page.

Summary

An IBAN is an international standard account number consisting of a country code, a check number and country-specific account information. The MOD-97 checksum it contains catches typing errors; but a valid IBAN does not show that the account is active. For the relationship of the IBAN with SEPA scope, see the Is an IBAN SEPA page.