An ABA number is a nine-digit code that identifies which bank holds your account
The ABA number (also called a routing number or routing transit number) tells the banking system which specific bank to send money to when you receive a wire transfer, direct deposit, or automatic payment. Every bank in the United States has its own ABA number. When you give someone your banking details for a transfer, you give them your ABA number along with your account number so the money reaches the right place.
ABA stands for American Bankers Association, the organization that originally assigned these codes. The number itself is printed on the bottom left of every check you receive from your bank. If you do not have a check handy, you can find your ABA number by logging into your online banking, calling your bank's customer service line, or searching the Federal Reserve's routing number database.
The nine digits break down into three groups of three. The first two digits identify the Federal Reserve district where your bank operates. The next three digits identify the specific bank or branch. The last four digits are a check digit and additional routing information. You do not need to understand this breakdown to use the number — you just need to know which number belongs to your bank.
Key Takeaways
- An ABA number is a nine-digit code that identifies your specific bank within the U.S. banking system.
- You need your ABA number and account number together to receive wire transfers, direct deposits, and automatic bill payments.
- Your ABA number appears on the bottom left of every check and is also available through your bank's website or customer service.
- Each bank has one ABA number, even if it has multiple branches, though some large banks may have different numbers for different divisions.
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 of the check — the first nine-digit number you see is your ABA number. The second set of numbers (usually longer) is your account number.
If you do not have a check, log into your online banking portal. Most banks display your routing number on the account details page or in a section labeled "Account Information" or "Wire Transfer Details." You can also call your bank's customer service number on the back of your debit card and ask for your routing number — they will give it to you over the phone.
The Federal Reserve maintains a public routing number database at frbservices.org. You can search by bank name and state to find the correct ABA number if you are unsure. This is useful if you are setting up a transfer to someone else's bank and need to verify you have the right number.
When you need to provide your ABA number
You provide your ABA number whenever someone needs to send money directly to your bank account. Common situations include setting up direct deposit for your paycheck, arranging automatic bill payments, receiving a wire transfer, or setting up a transfer from another bank account you own.
Insurance companies, government agencies, employers, and other organizations that send you refunds or payments often ask for your ABA number and account number so they can deposit money electronically. This is faster and more reliable than mailing a check. When you set up a payment online — such as paying a credit card bill or sending money to a friend through your bank's app — you may also need to provide the recipient's ABA number and account number.
You should never share your ABA number with someone you do not trust, though the number itself is not secret. It is printed on every check you write and is public information. What matters is that you do not share your account number with strangers, since the combination of ABA number and account number is what someone would need to access your account.
ABA numbers versus SWIFT codes and IBAN numbers
The ABA number works only within the United States. If you are receiving money from outside the U.S., you will need a SWIFT code instead. A SWIFT code is an international routing number that identifies your bank to the global banking system. Your bank can provide your SWIFT code if you need it for an international transfer.
Some countries use an IBAN (International Bank Account Number) instead of or in addition to a SWIFT code. An IBAN is a longer number that includes your country code, bank code, and account number all in one. U.S. banks do not use IBANs for domestic transfers, but if you are sending money to Europe or certain other regions, you may need to provide an IBAN instead of an ABA number.
For transfers within the United States, always use the ABA number. For transfers to other countries, ask your bank which code the receiving bank needs — usually a SWIFT code, sometimes an IBAN, and sometimes both.
What happens if you provide the wrong ABA number
If you give someone the wrong ABA number, the money will go to the wrong bank. The sending bank will try to deliver it to the account number you provided at that bank. If no matching account exists, the transfer may bounce back to the sender after a few business days. If an account with that number does exist at the wrong bank, the money could end up in someone else's account.
If you realize you gave the wrong ABA number, contact the sender immediately and ask them to cancel or recall the transfer if it has not yet been processed. Once money has been delivered to the wrong bank, you will need to contact that bank and ask them to help trace and return the funds. This can take weeks. The sender may also need to file a claim with their bank.
To avoid this problem, double-check your ABA number before giving it out. Verify it against a check, your online banking portal, or a call to your bank's customer service. If someone is sending you money and asks for your ABA number, provide it only after confirming it matches what your bank shows.
ABA numbers for different types of accounts
Most checking and savings accounts at the same bank share the same ABA number. Whether you have a checking account, savings account, or money market account at your bank, the routing number is the same. The ABA number identifies the bank, not the type of account.
However, some large banks operate multiple divisions or subsidiaries, each with its own ABA number. For example, a bank's online division might have a different routing number than its brick-and-mortar branches. If you have accounts at different divisions of the same bank, they may have different ABA numbers. Always check which number applies to the specific account you are using.
Credit unions also have ABA numbers. If you belong to a credit union, you can find your routing number the same way — on a check, through online banking, or by calling customer service. The process is identical to finding a bank's ABA number.
Frequently Asked Questions
Is my ABA number the same as my account number?
No. Your ABA number identifies your bank; your account number identifies your specific account at that bank. Both are needed together for transfers. On a check, the ABA number is the first nine digits at the bottom left, and your account number is the longer number that follows it.
Can I use the same ABA number for all my accounts at one bank?
Yes, if all your accounts are at the same bank branch or division. All checking, savings, and other accounts at that bank typically share one ABA number. If you have accounts at different divisions of a large bank, verify which ABA number applies to each account before setting up a transfer.
Do I need my ABA number to receive a check payment?
No. Checks do not require routing numbers — the bank name and account number on the check are enough. You only need your ABA number for electronic transfers like direct deposit, wire transfers, and automatic payments.
What if my bank merged with another bank?
After a merger, your bank may keep its original ABA number or switch to the acquiring bank's number. Your bank will notify you of any change and update your online banking to reflect the new routing number. If you are unsure after a merger, call your bank or check a recent check to confirm your current ABA number.
Can someone steal money from my account if they know my ABA number?
Knowing only your ABA number is not enough to access your account — a person would also need your account number. Even with both numbers, they cannot withdraw money without authorization. However, do not share your account number with people you do not trust, since the combination of ABA and account number is what appears on checks and transfer requests.