BSB Number means Bank State Branch (BSB) number which is a 6 digit bank code that identifies an individual branch of a bank and other financial institutions within Australia. This six digit number (BSB) plus the account number used to identify a particular account. BSB Numbers with account numbers combinations are used in domestic transaction only. For international transfers, a SWIFT code is also used in addition to the BSB number and a bank account number.

You may verify the BSB number by using the BSB lookup tool on bsbno.com –

BSB Number Lookup

The 6 digit BSB number is made up of three parts: AAB-CCC

The first two numbers (AA) specify the financial institution/bank.
The third number (B) indicates the state where the branch is located.
The last three numbers (CCC) are the unique identifier for a branch.

Financial Institution Codes (AA – First two Numbers)

Number	Code	Bank Name
1	ANZ	Australia and New Zealand Banking Group Ltd
03 or 73	WBC	Westpac Banking Corporation
06 or 76	CBA	Commonwealth Bank of Australia
08 or 78	NAB	National Australia Bank
10	BSA	BankSA
11	STG	St George Bank
12	BQL	Bank of Queensland
18	MBL	Macquarie Bank
24	CTI	Citibank
30	BWA	Bankwest
34	HBA	HSBC Bank Australia
48	MET	Suncorp-Metway
61		Adelaide Bank
633	BBL	Bendigo Bank
923	ING	ING Bank

State Codes (B – Third Number)

Code	State
2	Australian Capital Territory, New South Wales
3	Victoria
4	Queensland
5	South Australia & Northern Territory
6	Western Australia
7	Tasmania

Therefore, the BSB number for the Bankwest store in Perth, Western Australia (which has the identifying number 059), would be 306-059.

AA = 30 (Bankwest)
B = 6 (WA)
CCC = 059 (Perth)