The checksum enables the initiator of any transaction to perform a sanity check of any specified bank account number on their own computer prior to actually initiating a request. Money being transferred across international borders, the international network is used. Sorting code and BIC allocation
Members have ranges of sorting codes that they can allocate to bank offices. It identifies both the bank and the branch where the account is held. Subbranches have the same sorting code as the main bank office, but to uniquely identify them they have a two-digit suffix after the sorting code. The BBAN, whose format is decided by the national banking community, includes the domestic bank account number, branch identifier and potentially routing information, the only restrictions being that it must be of fixed length and that only case-insensitive alphanumeric characters are used.