The International Bank Account Number (IBAN) is an internationally agreed system of identifying bank accounts across national borders to facilitate the communication and processing of cross border transactions with a reduced risk of transcription errors. It was originally adopted by the European Committee for Banking Standards (ECBS), and later as an international standard under ISO 13616:1997. The current standard is ISO 13616:2007, which indicates SWIFT as the formal registrar. Initially developed to facilitate payments within the European Union, it has been implemented by most European countries and numerous countries in the other parts of the world, mainly in the Middle East and in the Caribbean. As of February 2016, 69 countries were using the IBAN numbering system.
The IBAN consists of up to 34 alphanumeric characters comprising: a country code; two check digits; and a number that includes the domestic bank account number, branch identifier, and potential routing information. The check digits enable a sanity check of the bank account number to confirm its integrity before submitting a transaction.
The IBAN consists of up to 34 alphanumeric characters, as follows:
- country code using ISO 3166-1 alpha-2 – two letters,
- check digits – two digits, and
- Basic Bank Account Number (BBAN) – up to 30 alphanumeric characters that are country-specific.
The check digits enable a sanity check of the bank account number to confirm its integrity before submitting a transaction.
The IBAN should not contain spaces when transmitted electronically. When printed it is expressed in groups of four characters separated by a single space, the last group being of variable length as shown in the example below:
Country IBAN formatting example
Germany DE44 5001 0517 5407 3249 31
Greece GR16 0110 1250 0000 0001 2300 695
United Kingdom GB29 NWBK 6016 1331 9268 19
Saudi Arabia SA03 8000 0000 6080 1016 7519
Switzerland CH93 0076 2011 6238 5295 7
Turkey TR33 0006 1005 1978 6457 8413 26
Permitted IBAN characters are the digits 0 to 9 and the 26 upper-case Latin alphabetic characters A to Z. This applies even in countries (e.g., Thailand) where these characters are not used in the national language.
Basic Bank Account Number
The Basic Bank Account Number (BBAN) format is decided by the national central bank or designated payment authority of each country. There is no consistency between the formats adopted. The national authority may register its BBAN format with SWIFT, but is not obliged to do so. It may adopt IBAN without registration. SWIFT also acts as the registration authority for the SWIFT system, which is used by most countries that have not adopted IBAN. A major difference between the two systems is that under SWIFT there is no requirement that BBANs used within a country be of a pre-defined length.
The BBAN must be of a fixed length for the country and comprise case-insensitive alphanumeric characters. It includes the domestic bank account number, branch identifier, and potential routing information. Each country can have a different national routing/account numbering system, up to a maximum of 30 alphanumeric characters.
The check digits enable the sending bank (or its customer) to perform a sanity check of the routing destination and account number from a single string of data at the time of data entry. This check is guaranteed to detect any instances where a single character has been omitted, duplicated, mistyped or where two characters have been transposed. Thus routing and account number errors are virtually eliminated.