Australian BSB Number Validator
Validate Australian Bank State Branch (BSB) numbers — checks format and bank code. Free, instant, runs in your browser.
BSB Number
Enter a BSB above to validate it
Sample Australian BSBs
012-003
ANZ
062-001
Commonwealth Bank
082-001
NAB
032-001
Westpac
192-001
Suncorp
About BSB numbers BSBs are real bank branch codes assigned by the Australian Payments Network (APN). The 6-digit code is split as XXX-XXX: the first two digits identify the bank, and the next four identify the branch. There is no mathematical check digit — validation relies on the bank code registry.
How to use it
- 1Enter a BSB number in the input field — formatted as XXX-XXX or as a plain 6-digit string.
- 2Click Validate to check the format and look up the bank code from the first two digits.
- 3If the BSB is valid, the tool identifies the bank it belongs to and explains the structure.
- 4Use the sample BSBs on the right to see how validation works for ANZ, Commonwealth Bank, NAB, and other major banks.
Common use cases
- Validate a BSB entered on a payment form before submitting a bank transfer.
- Check whether a BSB a customer provided belongs to a known Australian bank.
- Identify which bank owns a BSB for reconciliation or payment routing.
- Integrate BSB validation into an Australian payroll or payments application.
- Demonstrate the BSB format and bank code structure to developers new to Australian banking.
Frequently asked questions
- What is a BSB number?
- A BSB (Bank State Branch) number is a 6-digit code used in the Australian banking system to identify a specific bank and branch. It is required, along with the account number, for domestic bank transfers via BECS (Bulk Electronic Clearing System). The format is XXX-XXX: the first two digits identify the financial institution, and the remaining four identify the branch.
- How is a BSB validated?
- There is no mathematical check digit for BSBs — validation relies on checking that the number is exactly 6 digits and that the first two digits correspond to a known bank code in the Australian Payments Network (APN) registry. This tool checks those two conditions.
- What does the BSB tell me about the bank?
- The first two digits identify the financial institution (e.g. 01 = ANZ, 03 = Westpac, 06 = Commonwealth Bank, 08 = NAB). The next four digits identify the specific branch, but branch-level directory data is not publicly available — only the bank code is validated here.
- Is my BSB sent to a server?
- No. Validation happens entirely in your browser using a local lookup table of known bank codes. Nothing is uploaded or stored.
- Why does validation pass but the BSB is still rejected by my bank?
- This tool checks the format and bank code prefix only. A BSB that passes format validation may still be invalid if the branch no longer exists or the specific 4-digit branch code was never assigned. For authoritative lookups, use the BSB directory provided by your financial institution or the APN.
Try next
Australian Tax File Number (TFN) Validator
Validate Australian Tax File Numbers (TFN) — checks format and the official check-digit algorithm. No TFN generation to protect against misuse. Runs entirely in your browser.
Australian ABN Generator & Validator
Generate and validate Australian Business Numbers (ABN) using the official weighted checksum algorithm. Perfect for testing and development — runs entirely in your browser.
New Zealand Bank Account Number Validator
Validate New Zealand bank account numbers — checks the BB-BBBB-AAAAAAA-SS format, bank code, and overall structure.