IbanNet.Extensions.Bban

While IbanNet performs Mod-97 check digit validation on all IBAN's as defined by the IBAN standard (ISO 13616), it does not validate check digits of the Basic Bank Account Number (BBAN) section of an IBAN. Since there is no global standard for national bank accounts and as there are many different check digit algorithm variations (per country, sometimes even per bank), it was decided not to include this functionality in the core IbanNet package.

There is an extension package for IbanNet available in a separate GitHub repository with validation rules for BBAN check digits: IbanNet.Extensions.Bban. It is however near impossible for me to maintain this without community input so I am looking for contributors! If you wish to contribute to improve BBAN check digit validation support for IbanNet, please go ahead and check it out and reach out to me via that repository.