About BSB Numbers

A BSB number (or Bank/State/Branch number) is used for the purpose of abbreviating a customer's bank information. It is far easier to assign a customer a BSB number than to have a customer remember a large string of text. Instead, a short array of numbers is assigned in a block that can be easily deciphered by any bank or business to determine pertinent bank account information.

The First two digits specify the parent financial institution, the third digit specifies the state where the branch is located and the fourth, fifth and sixth digits specify the branch. For example, the BSB 033088 actually breaks down into the following.

03 = Westpac Banking Corporation
3 = Victoria
088 = 383 Chapel Street, Prahran

While banks usually follow this numbering convention, building societies and credit unions often don't, but it doesn't affect the way in which the bank details can be decoded. A financial institution may also use one centralised BSB for all accounts. For example, Suncorp uses 484799 for all deposit accounts regardless of which branch or state the account was opened.

As a general rule, BSB bank State information (the third digit in the BSB) will indicate its state of origin as dictated below:

  • 2 - Australian Capital Territory, New South Wales
  • 3 - Victoria
  • 4 - Queensland
  • 5 - South Australia, Northern Territory
  • 6 - Western Australia
  • 7 - Tasmania