IBANs

IBAN stands for International Bank Account Number, a standardized system for identifying bank accounts across borders to facilitate international payments. The IBAN is defined by ISO 13616 and is used by banks worldwide to route funds to the correct account.

An IBAN consists of a two-letter country code, two check digits, and a Basic Bank Account Number (BBAN) whose format is defined by the country. Total length ranges from 15 to 34 characters, depending on the country. For example, a German IBAN might look like DE89 3704 0044 0532 0130 00, and a UK example could be GB29 NWBK 6016 1319 2681 19.

The two check digits help validate the IBAN. To check validity, move the four initial characters to the end, convert letters to numbers (A=10, B=11, ..., Z=35), and compute modulo 97; a remainder of 1 indicates a valid IBAN.

Usage and scope: In cross-border payments, the IBAN identifies the beneficiary account, while a separate bank identifier (such as a SWIFT/BIC code) may be used to route the payment completely. Within SEPA, IBAN is the standard for euro transfers. Not all countries issue or accept IBANs, and some domestic transfers do not require them; always verify with the recipient's bank.