The routing number tells the payment system which bank to send your money to
The routing number on a check is a nine-digit code that identifies your specific bank or credit union. When someone deposits or cashes your check, that number directs the payment through the Federal Reserve's clearing system to the exact institution where your account lives. Without it, the check cannot move through the banking network.
You will find it in the bottom left corner of any check you write. It always appears before your account number, and it is always nine digits long. The routing number is the same for every check from the same account — it does not change when you order new checks or move to a different branch of the same bank.
The routing number is not secret. It is printed on every check you issue, and you can find it on your bank's website or by calling customer service. It is also called an ABA number, after the American Bankers Association, which originally assigned these codes in the 1910s.
Key Takeaways
- The routing number is a nine-digit code in the bottom left of your check that identifies which bank holds your account.
- It directs the check through the Federal Reserve's clearing system to your specific bank, not just any branch of that bank.
- The routing number is the same on every check from your account and is not confidential information.
- Different banks have different routing numbers, and some large banks have multiple routing numbers depending on which state or region the account was opened in.
- You need the routing number to set up direct deposit, wire transfers, or automatic bill payments from your account.
How the routing number moves your check through the banking system
When you write a check, the person who receives it deposits it at their own bank. That bank scans the routing number and uses it to find your bank in the Federal Reserve's database. The two banks then communicate through the clearing system — usually the Automated Clearing House (ACH) network or the Federal Reserve's own check clearing service — to move the money from your account to theirs.
The routing number is what makes this possible. Without it, the receiving bank would have no way to know where to send the request for payment. The account number alone is not enough, because account numbers are not unique across all banks — two different banks might both have an account numbered 123456789.
The entire process typically takes one to three business days, depending on when the check was deposited and which clearing system the banks use. The routing number is read during the first step, when the receiving bank scans the check.
Why different banks have different routing numbers
Large banks often have multiple routing numbers. Bank of America, for example, has different routing numbers for accounts opened in different states or regions. This is because routing numbers were originally assigned by geography — each Federal Reserve district had its own set of codes. The system has evolved, but the geographic structure remains.
Credit unions also have routing numbers, assigned by the CO-OP network or Shared Branch system rather than the Federal Reserve. If you bank at a credit union, your routing number will be different from any commercial bank's, even if you live in the same city.
Online banks and some newer financial institutions may use routing numbers assigned to partner banks that process their transactions. If you bank online, your routing number might belong to a bank you have never heard of — that is normal and does not affect how your account works.
Where to find your routing number if you do not have a check
If you have not ordered checks yet or have run out, you can find your routing number on your bank's website. Log into your account online and look for a section labeled "Account Details," "Routing Information," or "Wire Transfer Information." Most banks display it prominently.
You can also call your bank's customer service line and ask for your routing number. They will provide it when ready — there is no reason to keep it private. Some banks print it on statements or debit cards, though this is less common.
The Federal Reserve also maintains a public database of routing numbers. You can search by bank name and state on the Federal Reserve's website, though this is slower than asking your bank directly.
Routing numbers versus account numbers: what each one does
The routing number identifies the bank. The account number identifies your specific account within that bank. Together, they form a complete address for your money. Think of the routing number as the street address of the bank building, and the account number as your apartment number inside that building.
On a check, the routing number appears first (bottom left), followed by the account number (bottom center). Both are printed in magnetic ink that machines can read. The check number itself — printed in the top right — is separate and is used for your own record-keeping, not for moving the money.
When you set up direct deposit at work or automatic bill payments, you will need to provide both numbers. The routing number tells the system which bank to contact, and the account number tells that bank which account to deposit into or withdraw from.
What happens if you use the wrong routing number
If a check has an incorrect routing number, it will be rejected during clearing. The receiving bank will not be able to find your bank in the system, and the check will be returned to the person who tried to deposit it. They will then contact you to ask for a corrected check.
This can delay payment by several days. If you are paying a bill by check and the routing number is wrong, the payment will not go through, and you may face a late fee from the creditor. For this reason, it is important to verify the routing number before writing a large check or setting up automatic payments.
If you have already written checks with an incorrect routing number, contact your bank when ready. They can tell you whether the checks will clear or be rejected. In most cases, you will need to issue new checks with the correct routing number.
Routing numbers for wire transfers and ACH payments
When you send a wire transfer or set up an ACH payment (like direct deposit or bill pay), you will be asked for a routing number. The routing number you use depends on the type of transfer. For ACH payments, you use your standard routing number — the same one on your checks. For wire transfers, some banks use a different routing number called a wire routing number.
Wire routing numbers are less common now, but some large banks still maintain them. If you are sending a wire transfer, ask your bank whether to use your regular routing number or a separate wire routing number. Using the wrong one will cause the transfer to fail or be delayed.
International wire transfers require additional information beyond the routing number — usually a SWIFT code for the receiving bank and sometimes an IBAN (International Bank Account Number). The routing number alone is not sufficient for money leaving the United States.
Frequently Asked Questions
Is the routing number on my check the same as my bank's main routing number?
Not always. Large banks have multiple routing numbers by region or account type. The routing number printed on your specific check is the correct one for your account. If you need to verify it, check your bank's website or call customer service with your account number.
Can someone use my routing number to steal money from my account?
The routing number alone is not enough to access your account. A person would also need your account number and would typically need authorization from you or a court order. The routing number is printed on every check you write, so it is not considered confidential information.
What if my bank merged with another bank — does my routing number change?
Usually not when ready. Banks often keep the original routing number for existing accounts even after a merger. However, new checks ordered after the merger might have a different routing number. Contact your bank to confirm whether your routing number has changed.
Do I need a routing number to receive a wire transfer?
Yes. The person sending you the wire will need your routing number and account number. Some banks also ask for your full name and address to match against the account. Ask your bank for the correct wire routing number if it differs from your regular routing number.
Why do credit unions have different routing numbers than banks?
Credit unions are not part of the Federal Reserve system in the same way banks are. Their routing numbers are assigned by the CO-OP network or other credit union clearing systems. The process works the same way — the routing number directs the payment to your credit union — but the numbering system is separate.