The routing number is printed at the bottom left of your check, in the first group of nine digits
Every check has three sets of numbers printed along the bottom edge in magnetic ink. The first set, on the far left, is your routing number—a nine-digit code that identifies which bank or credit union issued your account. It comes before your account number and the check number.
The routing number stays the same for every check you write from that account. If you have multiple accounts at the same bank, they may share the same routing number, or the bank may assign different ones depending on the account type or branch. The only way to know for certain is to look at the actual check in front of you.
You need the routing number when you set up direct deposit, arrange wire transfers, or authorize automatic payments. It tells the receiving bank exactly where to pull the money from.
Key Takeaways
- The routing number is the first nine-digit group printed at the bottom left of your check, separated by special symbols.
- Each bank and credit union has its own routing number, though some large institutions use multiple numbers for different regions or account types.
- You can also find your routing number on your bank's website, by calling customer service, or through the ABA routing number lookup tool.
- The routing number is different from your account number, which appears in the second group of digits on your check.
How to read the numbers at the bottom of a check
The bottom of a check displays three separate number sequences, each enclosed or separated by special symbols that look like colons or brackets. From left to right, you see the routing number first, then your account number, then the check number.
The routing number uses a specific format: the first four digits identify the Federal Reserve district and the bank's location, the next four identify the specific bank or branch, and the final digit is a check digit that verifies the number is correct. You do not need to understand this breakdown—you only need to copy all nine digits exactly as printed.
The magnetic ink used to print these numbers allows bank machines to read them automatically during processing. If you are writing down the routing number by hand, take care to copy it precisely. A single digit wrong will send the payment to the wrong place.
What to do if your check does not show a routing number
Starter checks, temporary checks, or checks from a new account sometimes arrive without the routing number printed. This is rare but does happen. If your check is blank in that spot, do not guess or leave it blank—contact your bank directly.
Call the customer service number on the back of your debit card or visit your bank's website. You can also visit a branch in person with your ID and a blank check. The bank will tell you the correct routing number for your account and can print new checks with the number included if needed.
Some online banks or credit unions that do not issue physical checks still have routing numbers. If you need one and have no checks, your bank's website usually lists it under account information or settings. If not, a phone call to customer service will get you the answer in minutes.
Finding your routing number without a check
You do not need a physical check to find your routing number. Most banks display it in the online banking portal under account details, settings, or a section labeled "Routing Information." Log in, navigate to your account information, and look for a field that says "routing number" or "ABA number."
If your bank does not list it online, call the customer service number on your debit card or bank statement. Have your account number ready, and the representative will give you the routing number over the phone in seconds.
The American Bankers Association (ABA) also maintains a free routing number lookup tool on its website. Enter your bank name and state, and the tool will return the routing number. This works for almost every bank and credit union in the United States.
Routing numbers versus account numbers
The routing number and account number are two different things, and you need both for most money transfers. The routing number identifies your bank; the account number identifies your specific account within that bank. On a check, the routing number comes first (nine digits), and the account number comes second (usually ten to twelve digits, but this varies by bank).
Think of it this way: the routing number is like the address of the bank building, and the account number is like your apartment number inside that building. A wire transfer or direct deposit needs both pieces of information to land in the right place.
If you give someone only the routing number without the account number, the money cannot reach you. If you give only the account number without the routing number, the receiving bank will not know which institution to contact. Always provide both when requested.
Why banks use routing numbers
Routing numbers exist because the U.S. banking system is decentralized. There is no single national bank—instead, thousands of separate banks and credit unions operate across the country. When you write a check or set up a direct deposit, the payment has to travel from one bank to another, sometimes across state lines.
The routing number tells the Federal Reserve and the receiving bank which institution holds your account. Without it, the system would have no way to know whether a check drawn on "First National Bank" should go to the branch in Ohio or the one in California. The routing number solves this by being unique to each bank and, in some cases, to each branch.
The same logic applies to electronic transfers. When you authorize an automatic payment or direct deposit, the routing number ensures the money moves to the correct financial institution on the correct schedule.
Common mistakes when using routing numbers
The most common error is transposing digits—writing 021000021 instead of 021000012, for example. A single digit wrong sends the payment to a different bank entirely. Always double-check what you have written or typed before submitting it.
Another mistake is confusing the routing number with the check number. The check number appears on the far right of the bottom line and is usually only four digits. This number identifies that specific check within your account, not your bank. Do not use it in place of the routing number.
Some people also assume that all branches of the same bank share the same routing number. This is usually true, but not always. Large banks sometimes assign different routing numbers to different regions or account types. If you have moved or changed account types, verify the routing number on your current check rather than relying on one from an old check.
Frequently Asked Questions
Can I use the routing number from an old check?
Usually yes, but not always. If you still have an account at the same bank and have not moved to a different region or account type, the routing number should be the same. However, banks occasionally change routing numbers during mergers or reorganizations. To be safe, use the number from your most recent check or verify it with your bank before submitting it.
What if I give someone the wrong routing number?
The payment will be sent to a different bank. The receiving bank will likely reject it and return it to the sender, which can take several days. Contact your bank immediately if this happens. They can sometimes trace the payment and reroute it, but the process is not fast. Always verify the routing number before submitting it.
Do credit unions have routing numbers?
Yes. Credit unions issue checks with routing numbers just like banks do. The routing number appears in the same location at the bottom left of the check. If you need your credit union's routing number and do not have a check, call the credit union or check its website.
Is the routing number the same as the SWIFT code?
No. The routing number is used for domestic transfers within the United States. The SWIFT code (also called a BIC code) is used for international wire transfers. If you are sending money to another country, you will need the SWIFT code, not the routing number. Your bank can provide the SWIFT code if you ask.
Can someone steal money using just my routing number?
Not with the routing number alone. A thief would also need your account number to access your account. However, do not share either number with people you do not trust. Treat your routing and account numbers the way you would treat your address and apartment number—they are not secret, but you should not post them publicly or give them to strangers.