Your bank's ABA number is a nine-digit code that identifies which bank you use

An ABA number (also called a routing number) is a unique identifier assigned to your bank by the American Bankers Association. Think of it like your bank's address in the financial system. When money moves from one bank to another — whether you're setting up direct deposit, sending a wire transfer, or paying a bill online — the ABA number tells the sending bank exactly where to send that money.

Every bank in the United States has its own ABA number. If you have accounts at two different banks, each one has a different ABA number. Some larger banks may have multiple ABA numbers if they operate different divisions or acquired other banks.

The ABA number is not secret and not sensitive. You can share it freely. It only tells someone which bank holds your account — it does not let them access your money or identify which specific account is yours.

Key Takeaways

  • Your ABA number is a nine-digit code printed on the bottom left of your checks and available from your bank's website or customer service.
  • You need your ABA number whenever money moves between banks, including direct deposit setup, wire transfers, and bill payments.
  • The ABA number identifies only your bank, not your individual account — you also need your account number for most transactions.
  • The first four digits of an ABA number identify the Federal Reserve district where your bank is located.

Where to find your ABA number

The easiest place to find your ABA number is on a check from your checking account. Look at the bottom left corner of the check — you will see nine digits printed there. The first nine digits are your ABA number. (The longer number on the right is your account number.)

If you do not have checks, you can find your ABA number by logging into your bank's website or mobile app — it is usually listed in the account details or settings section. You can also call your bank's customer service line and ask them directly. They will give it to you over the phone without asking security questions, because it is not confidential information.

Some banks print the ABA number on statements or deposit slips as well, though this varies by bank.

When you need to provide your ABA number

You will need your ABA number whenever someone outside your bank needs to send money to your account. The most common situations are:

  • Direct deposit: Your employer or a government agency (like Social Security) needs your ABA number and account number to deposit paychecks or benefits directly into your account.
  • Wire transfers: If someone is sending you money through a wire transfer, they will need your ABA number, account number, and your name.
  • Bill payments: When you set up automatic bill payments through your bank's website, you may need to provide the ABA number of the company receiving the payment.
  • ACH transfers: ACH (Automated Clearing House) transfers — the system used for most online money movements between accounts — require your ABA number and account number.

In all these cases, you are providing your ABA number to the sending bank or organization, not to your own bank. Your own bank already knows its own ABA number.

ABA number vs. account number: what is the difference

Your ABA number identifies your bank. Your account number identifies your specific account within that bank. You need both pieces of information for most transactions.

Think of it this way: the ABA number is like the address of a post office, and your account number is like your mailbox number inside that post office. The ABA number tells the money where to go. The account number tells it which mailbox to put it in.

On a check, the ABA number is the first nine digits at the bottom left. The account number is the longer number to the right of that. Both are printed in a special magnetic ink so banks can read them automatically.

What the nine digits mean

The nine digits of an ABA number are not random. The first four digits identify the Federal Reserve district where your bank is located. The next four digits identify your specific bank within that district. The last digit is a check digit — a mathematical verification that the number is valid.

You do not need to decode your ABA number yourself. Banks and payment systems do this automatically. But if you are curious whether a number is real, you can use an ABA lookup tool online to see which bank it belongs to.

ABA numbers for different types of accounts

If you have multiple accounts at the same bank — for example, a checking account and a savings account — they share the same ABA number. The ABA number identifies the bank, not the individual account.

However, if you have accounts at different banks, each bank has its own ABA number. A credit union will have a different ABA number than a commercial bank, even if they are in the same town.

Online banks and traditional banks both have ABA numbers. The process for finding it is the same: check your checks, log into your account online, or call customer service.

What you should not do with your ABA number

Because your ABA number is not sensitive information, there is little risk in sharing it. However, you should not give it to someone unless they have a legitimate reason to receive money into your account or send money from it.

If someone asks for your ABA number along with your full account number, full name, and date of birth all at once, be cautious. That combination of information could potentially be used to set up unauthorized transfers. Legitimate organizations usually ask for these pieces of information separately and over find channels.

Your bank will never ask you for your ABA number. They already know it.

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. You may see one term on your checks and another on your bank's website, but they refer to the same nine-digit code.

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

No. Your ABA number alone cannot be used to access or transfer money from your account. A person would also need your account number and usually your name. Even with all three pieces of information, most banks require additional verification before processing transfers.

Do I need a different ABA number for my savings account and checking account?

No. Both accounts at the same bank share the same ABA number. The ABA number identifies the bank. Your account number identifies which specific account the money should go into.

What if I cannot find my ABA number?

Call your bank's customer service line — they can tell you your ABA number in seconds. You can also visit a branch in person and ask. There is no charge for this information.

Does my ABA number change if I move to a different state?

No. Your ABA number is tied to your bank, not your location. If you move and keep the same bank account, your ABA number stays the same. If you switch to a different bank, you will have a new ABA number.