BSB Decoder

Enter any BSB number to see a visual breakdown of what each digit means — the institution, state, and branch.

How BSB Numbers Work

Every Australian BSB number is a 6-digit code in the format XXX-YYY. These digits aren't random — each group carries specific meaning:

Digits Meaning Example (062-000)
1–2 Financial institution 06 = Commonwealth Bank
3 State or territory 2 = NSW
4–6 Branch number 000 = Head office

For a full explanation, see our guide: BSB Number Format Explained.

Frequently Asked Questions

Does the state digit always match the branch location?

The state digit convention (digit 3) is most reliably followed by the Big 4 banks (ANZ, Westpac, CBA, NAB). Smaller banks, credit unions, and online-only institutions may not follow this pattern. Always verify with the actual branch details.

What do the first two digits tell you?

The first two digits identify the financial institution. For example, 06 is Commonwealth Bank, 01 is ANZ, 03 is Westpac, and 08 is NAB. Each bank or financial institution is assigned one or more two-digit prefixes.

Can two different banks have the same prefix?

No — each two-digit prefix is allocated to a single institution. However, a single bank can have multiple prefixes. For example, Commonwealth Bank uses both 06 and 76, and Westpac uses both 03 and 73.