Your ABA number is your bank's routing number — a nine-digit code that tells the financial system which bank to send money to
The ABA number and the routing number are the same thing. ABA stands for American Bankers Association, the organization that created the system. When you set up a direct deposit, send a wire transfer, or arrange an automatic payment, you give the sender your routing number so they know which bank holds your account. Without it, the money goes nowhere.
Your ABA number is specific to your bank and its location — not to you personally. If you have accounts at two different banks, each one has its own ABA number. If you have multiple accounts at the same bank branch, they all share the same ABA number. The number itself is printed on the bottom left of your checks, and you can also find it on your bank's website or by calling customer service.
Key Takeaways
- Your ABA number is a nine-digit code that identifies your specific bank, not your individual account.
- The ABA number appears on the bottom left of your checks, before your account number.
- You need your ABA number and account number together to receive direct deposits, wire transfers, and automatic payments.
- If you switch banks or open an account at a different branch, you may get a different ABA number even if you stay with the same bank.
Where to find your ABA number
The easiest place to find your ABA number is on a check from your account. Look at the bottom left corner — you will see nine digits printed there. That is your ABA number. The next set of digits to the right is your account number.
If you do not have checks handy, log into your bank's website or mobile app. Most banks display the routing number in the account details section, sometimes labeled "routing number" or "ABA number." You can also call your bank's customer service line and ask for your routing number — they will give it to you in seconds.
Some banks print the routing number on statements as well, though not all do. If you cannot find it anywhere else, the bank's website usually has a tool where you can search by state and bank name to look up the routing number.
Why banks need your ABA number
The ABA number is part of the infrastructure that moves money between banks. When your employer sends your paycheck via direct deposit, they use your ABA number to route the funds to your bank, then your account number tells the bank which account within that bank receives the money. Without the ABA number, the system would not know which of thousands of banks across the country should receive the transfer.
Wire transfers, automatic bill payments, and ACH transfers (the system used for most routine electronic payments) all require your ABA number. If you give someone the wrong ABA number, the money will go to the wrong bank — and getting it back can take days or weeks. That is why it is important to double-check the number before you hand it over.
The difference between ABA number and account number
Your ABA number identifies your bank. Your account number identifies your specific account within that bank. Together, they form a complete address for your money. Think of it like a mailing address: the ABA number is the city and state, and the account number is the street address and apartment number.
When you set up direct deposit or give someone your banking information, you need both numbers. If you only give the ABA number, the sender knows which bank to contact but not which account to deposit into. If you only give the account number, the sender has no way to know which bank to use. Both pieces are required for the transaction to work.
What happens if you use the wrong ABA number
If you provide an incorrect ABA number, the money will be sent to the wrong bank. The sending bank will process the transfer to the routing number you gave them, and the receiving bank will deposit it into the account number you provided — but at their institution, not yours. Your money ends up in someone else's bank account.
Most of the time, the error is caught quickly and the funds are returned to the sender. However, this can take several business days. If the account number you provided happens to exist at the wrong bank, the money may sit there until someone notices the mistake. To avoid this, always verify both your ABA number and account number before giving them to anyone, and ask the person sending the money to confirm they have the correct information.
ABA numbers and different bank branches
Some large banks have different ABA numbers for different regions or branches. If you move to a different state and open an account at the same bank, you might receive a new ABA number. This happens because the routing system is organized partly by geography, and some banks maintain separate routing numbers for different areas.
However, many national banks use the same ABA number across all their branches. The only way to know for sure is to check the routing number on your new account's checks or in your online banking portal. If you are unsure whether your ABA number has changed, contact your bank directly — they can confirm whether your old routing number still works or if you need to update it with your employer or creditors.
Frequently Asked Questions
Is my ABA number the same as my SWIFT code?
No. Your ABA number is used for domestic transfers within the United States. A SWIFT code is used for international wire transfers and identifies your bank globally. If you are sending or receiving money from outside the U.S., you will need a SWIFT code instead of an ABA number.
Can I use the same ABA number for all my accounts at the same bank?
Yes, if all your accounts are at the same branch. All accounts at one branch share the same ABA number. However, if you have accounts at different branches or different banks, each one will have its own ABA number. Always verify which account number goes with which routing number before setting up a transfer.
What if my bank merged with another bank?
Your ABA number may change after a merger. The acquiring bank sometimes assigns new routing numbers to accounts from the bank that was acquired. Contact your bank to confirm your current ABA number, and update it with your employer and any creditors who have it on file.
Do I need my ABA number to receive a tax refund?
Yes. If you want your tax refund deposited directly into your checking account, you will need to provide both your ABA number and your account number on your tax return. The IRS uses this information to deposit the refund into the correct account at the correct bank.
Can someone steal money from my account if they have my ABA number?
Not with just your ABA number alone. They would also need your account number, and even then, most banks require additional verification before processing transfers. However, do not share your full banking information with people you do not trust. Only provide your ABA and account numbers to employers, government agencies, and businesses you are actively working with.