Before IBAN, differing national standards for bank account identification (i.e.bank, branch, routing codes, and account number) were confusing for some users.It also does not contain check digits, so errors of transcription were not detectable and it was not possible for a sending bank to validate the routing information prior to submitting the payment.Routing errors caused delayed payments and incurred extra costs to the sending and receiving banks and often to intermediate routing banks.Note: If the modulus check shows the account number as valid, this means that the account number is a possible account number for that sorting code but is not necessarily in use.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.This proposal had a degree of flexibility, which the European Committee for Banking Standards (ECBS) believed would make it unworkable, and they produced a "slimmed down" version of the standard which, amongst other things, permitted only upper-case letters and required that the IBAN for each country have a fixed length.
As an on-screen “floater”, it allows the user to key in a sort code and account number combination and the software will immediately validate, giving a pass or fail verdict.
Modulus Checker is software developed by Ardbrook Limited and, with our unrivalled 25 year experience of the Irish Banking sector that enables the user to validate the accuracy of any sort code / bank account number combination, for the clearing banks within the Republic of Ireland and Northern Ireland; Credit Unions and most other non-associated banks.
This is achieved by running in reverse the internal algorithms of each of the clearing banks on the sort code / bank account numbered entered.
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. SWIFT also acts as the registration authority for the SWIFT system, which is used by most countries that have not adopted IBAN.