A BSB is a six-digit code that identifies which bank branch holds your account

BSB stands for Bank Sort Code in the United Kingdom and Ireland. It is a six-digit number that tells the banking system which specific branch of which bank you use. When you make a payment to someone else's account—whether by transfer, standing order, or direct debit—you give the receiving bank this code so the money goes to the right place.

The first four digits identify the bank itself. The last two digits identify the specific branch. So if your BSB is 20-00-00, the "20-00" part means your bank, and the final "00" means a particular branch location. Different branches of the same bank have different BSBs, though many modern accounts use a single BSB for the entire bank rather than individual branches.

You will find your BSB printed on the bottom left of your cheques, on your bank statements, and in your online banking portal. If you cannot find it, your bank's customer service can tell you in seconds.

Key Takeaways

  • A BSB is a six-digit code that identifies your bank and branch; you need it whenever someone sends you money or you set up a payment to another account.
  • The first four digits identify the bank, and the last two identify the branch, though many banks now use a single BSB for all customers.
  • You can find your BSB on cheques, bank statements, online banking, or by calling your bank.
  • Giving the wrong BSB will send money to the wrong account, so double-check before confirming any payment.
  • BSB codes are only used in the UK and Ireland; other countries use different routing systems like SWIFT codes or routing numbers.

Where you will see your BSB and how to find it

Your BSB appears in several places. On a paper cheque, it is printed at the bottom left in the format XX-XX-XX (for example, 30-66-77). On your bank statement—whether printed or online—it will be listed near your account number. Most online banking portals show it under account details or account information.

If you have lost track of it or cannot find it anywhere, ring your bank's customer service line. They will confirm it over the phone once they have verified your identity. You can also ask for it in a branch if you prefer to do so in person.

Some banks print the BSB and account number together on a payment card or reference card they send with your account opening pack. If you kept that card, you have both numbers in one place.

When you need to provide your BSB

You need your BSB whenever someone outside your bank sends you money. This includes salary payments from an employer, refunds from a business, or transfers from friends and family. The person sending the money needs both your BSB and your account number to route the payment correctly.

You also need to know the receiving bank's BSB when you send money to someone else. If you are setting up a standing order (a regular automatic payment) or a direct debit (where a business takes money from your account on an agreed schedule), you will need the recipient's BSB and account number.

Online payment services, bill payment systems, and peer-to-peer transfer apps all ask for BSB and account number before processing a transfer. Some apps will look up the account holder's name once you enter these details, which is a safety check to make sure you are sending money to the right person.

What happens if you give the wrong BSB

If you provide an incorrect BSB, the payment will go to the wrong bank or branch. The money may end up in another person's account, or it may be rejected by the receiving bank if the BSB does not match any real account.

If money is sent to the wrong account by mistake, you will need to contact your bank and ask them to trace the payment. They can contact the receiving bank and ask them to return the funds. This process can take several days or weeks, and there is no may provide the receiving bank will cooperate quickly, especially if the money has already been moved or spent.

To avoid this, always double-check the BSB before you confirm a payment. Many online banking systems now show the account holder's name once you enter the BSB and account number, which gives you a chance to verify you are sending money to the right person before the transaction goes through.

BSB versus account number and other payment codes

Your account number is different from your BSB. The account number is typically 8 digits and identifies your specific account within that bank. Together, the BSB and account number form a unique pair that points to your account and no one else's. You always need both to send or receive money.

In other countries, different systems are used. The SWIFT code (also called a BIC code) is used for international transfers and identifies a bank worldwide. A routing number is used in the United States for domestic transfers. IBAN (International Bank Account Number) is used across Europe and combines the BSB, account number, and country code into a single standardised format.

If you are sending money internationally from the UK, you may need the recipient's SWIFT code or IBAN instead of their BSB, depending on which country they bank in and which payment method you use.

How BSB codes are structured and assigned

The six digits of a BSB break down into two parts. The first four digits are the bank code, which identifies the financial institution. For example, all Barclays accounts start with 20, all HSBC accounts start with 40, and all Lloyds accounts start with 30. These codes are assigned by Vocalink, the organisation that manages the UK's payment system.

The last two digits originally identified the specific branch location. A bank with branches across the country would have different BSBs for London, Manchester, Glasgow, and so on. However, most modern banks have consolidated their branch networks and now use a single BSB for all customers, regardless of where they live or which branch they use.

Some banks still maintain multiple BSBs for historical reasons or for specific services (such as a separate BSB for business accounts), but this is becoming less common. When you open an account, your bank will assign you a BSB; you do not choose it.

Keeping your BSB safe and what not to share

Your BSB is not secret information. You must share it with anyone who needs to send you money, and it appears on cheques and statements that may be seen by others. However, you should not share it carelessly or with people you do not trust.

A scammer who has your BSB and account number can set up a direct debit or standing order against your account without your permission if they also have other personal details. They cannot withdraw cash or transfer money out directly, but they can authorise regular payments to themselves. If this happens, contact your bank immediately and ask them to cancel the unauthorised instruction.

Never give your BSB to someone who calls you claiming to be from your bank, even if they already know other details about your account. Your bank will never ask you to confirm your BSB over the phone; they already have it on file.

Frequently Asked Questions

Can I change my BSB?

No, you cannot change your BSB. It is assigned by your bank and identifies which bank and branch (or banking service) holds your account. If you switch banks, your new bank will assign you a new BSB. If you move branches within the same bank, your BSB may stay the same or change depending on the bank's system.

Do I need a different BSB for each account I hold?

Not necessarily. If you hold multiple accounts at the same bank, they may share the same BSB but have different account numbers. Each account number is unique, so the combination of BSB and account number still identifies each account separately. Check your statements or online banking to see which BSB applies to each account.

What if someone asks for my BSB but I do not recognise them?

If a business or person asks for your BSB and you are unsure whether they are legitimate, ask them why they need it and how they will use it. Legitimate businesses will explain clearly. If you are still uncertain, contact your bank directly using a phone number from their official website or a statement, not a number the person gives you.

Is my money safe if I give someone my BSB and account number?

Your BSB and account number alone are not enough for someone to steal money from your account. They cannot withdraw cash or make a one-off transfer without additional authorisation. However, they could set up a direct debit or standing order if they also have your name and address. If you suspect unauthorised activity, contact your bank immediately.

Do I need a BSB to receive money from abroad?

For international transfers, the sender may need your IBAN or SWIFT code instead of your BSB, depending on which country they are sending from and which payment method they use. Your bank can provide both your IBAN and SWIFT code. Ask your bank which code to give to someone sending money from outside the UK.