ABA is your bank's routing number, printed on the bottom left of your checks

ABA stands for American Bankers Association. An ABA number is a nine-digit code that identifies which bank or credit union holds your account. It tells the payment system where to send money when you receive a transfer, and where to pull money from when you send one. Every bank and credit union in the United States has its own ABA number.

You will see it printed on the bottom left corner of your checks, right before your account number. If you do not have checks, you can find it by logging into your online banking, calling your bank, or looking at a deposit slip. The ABA number stays the same for your bank regardless of which branch you use or how many accounts you have there.

The ABA number is different from your account number. Your account number identifies your specific account. The ABA number identifies your bank. Together, they tell the payment system exactly where your money is.

Key Takeaways

  • ABA numbers are nine-digit codes that identify your bank or credit union, not your individual account.
  • You need your ABA number and account number together to receive wire transfers, ACH payments, and direct deposits.
  • The ABA number appears on the bottom left of your checks and does not change if you move branches or open new accounts at the same bank.
  • Different banks have different ABA numbers, even if they are part of the same larger financial institution or have the same name in different states.

When you need to give out your ABA number

You provide your ABA number and account number whenever someone needs to send you money electronically. This includes direct deposits from your employer, tax refunds from the IRS, payments from government programs, and transfers from other people's bank accounts. You also need it if you are setting up automatic bill payments or moving money between your own accounts at different banks.

You do not need to give out your ABA number for everyday debit card purchases, credit card payments, or checks you write. Those transactions use different routing systems. However, if someone is paying you by ACH transfer or wire, they will ask for both your ABA number and your account number.

Some online payment platforms and peer-to-peer apps (like Venmo or PayPal) do not require your ABA number at all—they use your email or phone number instead. But traditional bank-to-bank transfers always need it.

How the ABA number moves your money

When money moves between banks, it travels through a network called the ACH (Automated Clearing House) or through wire transfer systems. The ABA number is the address that tells these systems which bank to contact. Without it, the payment system would not know where to deliver the money.

Here is what happens: Your employer's payroll system takes your ABA number and account number, bundles it with thousands of other employees' information, and sends it to the ACH network. The ACH network reads the ABA number, finds your bank, and delivers your deposit. The whole process usually takes one to two business days.

If the ABA number is wrong, the payment either bounces back to the sender or gets deposited into the wrong account. This is why it is critical to double-check it before giving it out, especially for large transfers.

ABA numbers are not the same as SWIFT codes or IBAN numbers

ABA numbers only work for transfers within the United States. If you are receiving money from outside the country, you will need a different code. International transfers use SWIFT codes (also called BIC codes) to identify banks worldwide, and some countries use IBAN numbers (International Bank Account Numbers) instead of account numbers.

Your bank can provide both your ABA number and your SWIFT code if you need them. They are not interchangeable—a SWIFT code will not work for a domestic ACH transfer, and an ABA number will not work for an international wire.

What happens if you give out your ABA number

Your ABA number is public information. It is printed on your checks, which you hand to people regularly. Giving it out does not put your account at risk by itself, because someone also needs your account number to actually move money.

However, you should never give out your ABA number and account number together to someone you do not trust. If a scammer has both, they can set up unauthorized ACH transfers or bill payments from your account. If you only give out your ABA number, or if someone has just your account number without the ABA number, they cannot complete a transfer on their own.

If you suspect fraud or unauthorized transfers, contact your bank immediately. Banks have fraud protection for ACH transfers, and you may be able to reverse unauthorized payments within a certain window—usually 60 days for ACH disputes.

How to find your ABA number

The easiest place to look is the bottom left of one of your checks. The first nine digits are your ABA number. The next set of numbers is your account number.

If you do not have checks, log into your online banking portal. Most banks display your ABA number (sometimes called your routing number) in the account details or transfer settings section. You can also call your bank's customer service line and ask for your routing number—they will give it to you over the phone.

Some banks print the ABA number on deposit slips or statements. If you are having trouble finding it, your bank's website usually has a tool where you can search for the ABA number by entering your bank name and state.

ABA numbers for different branches and accounts

If your bank has multiple branches, they all share the same ABA number. You do not need a different routing number for each location. This is true even if the branches are in different states or cities.

If you have multiple accounts at the same bank—a checking account and a savings account, for example—they both use the same ABA number. The account number is what distinguishes between them. So you would give the same ABA number for both accounts, but different account numbers.

However, if you have accounts at two completely different banks, each bank has its own ABA number. A Bank of America account and a Wells Fargo account will have different ABA numbers, even if both banks operate in your state.

Frequently Asked Questions

Is my ABA number the same as my routing number?

Yes. ABA number and routing number are the same thing. Banks use both terms interchangeably. It is the nine-digit code that identifies your bank for electronic transfers.

Can someone steal money from my account if they only have my ABA number?

No. They also need your account number to move money. Your ABA number alone identifies the bank, not your specific account. However, never give both numbers to someone you do not trust.

Do I need my ABA number to use my debit card?

No. Debit card transactions do not use your ABA number. You only need it for electronic transfers, direct deposits, and ACH payments—not for everyday card purchases.

What if I give someone the wrong ABA number?

The payment will either bounce back to the sender or go to the wrong bank. The sender will be notified that the transfer failed, and they can resend it with the correct number. Contact your bank if you are unsure whether a payment went through.

Do credit unions have ABA numbers?

Yes. Credit unions have their own ABA numbers just like banks do. You will find it the same way—on checks, in online banking, or by calling the credit union directly.