People have Social Security numbers. Cities and towns have zip codes. Banks have routing numbers, bank account numbers and check numbers. They're sometimes referred to as ABA routing numbers, routing transit numbers or simply as RTNs. The routing number identifies the bank where the account was opened, as well as its location. It is this number that sets it apart from all the other financial institutions out there.
ABA stands for the American Banker’s Association, which developed the routing number system in 1910 and still oversees it today.
When You Pay by Check
Banks need ID numbers to avoid chaos, confusion and mistakes when funds that have been placed on deposit with them are transferred from one institution to another, such as when someone writes a check for payment. The Federal Reserve Bank requires that the bank’s name, as well as its city and state location, also appear on paper checks in addition to the bank’s routing number. The paying bank must be clearly identified.
This makes sense when you think about it. Fewer and fewer people use paper checks these days, but literally billions of them have nonetheless been written in the last decade. The federal government and the ABA want to make absolutely sure that the money comes out of your account and no one else's when you remit $150 to your electric company for this month’s service.
Most checks are electronically processed these days, even the paper kind. Scanners literally snap pictures of the front and back of checks to identify transactions. Assuming the money is there and available in your checking account, that image will facilitate an electronic debit of that $150 from your bank account and transfer it to your electric company’s account. The routing number on your check guides this process to the correct bank, not to one with a similar or the same name in another state.
Read More: Step-by-Step: How to Write a Check
How Routing Numbers Work
A bank’s routing number is composed of nine digits. These numbers work together to clearly identify the bank, as well as the location where the account was opened and is being held. Joe’s Bank in Omaha might have a routing number of 123456789. Joe’s Bank in Topeka would be differentiated with a routing number of 123456710. The last two digits are different because the branches are in different states.
One bank can have multiple routing numbers if it has more than one location, each number identifying a certain branch. The routing number works in conjunction with your account number to clearly identify where the money is to be transferred from.
Routing numbers work in reverse as well. They identify the account into which the money is supposed to be deposited after it leaves your account.
When a Routing Number Is Used
Routing numbers aren’t reserved only for old-fashioned paper checks. They facilitate electronic transfers of money as well. You’ll certainly be asked for it, along with your account number, if you’re trying to pay that electric bill online or over the phone. You’ll need it if you set up automatic debits from your account to pay recurring monthly bills. And you’ll have to give it to your employer if your paychecks are issued to you by direct deposit so the company knows where to send your money.
Mobile payment services like Venmo and PayPal also require a routing number if you want to transfer money to a family member or friend, and wire transfers require this identifier as well.
Where to Find Your Bank’s Routing Number
Maybe you gave up on paper checks years ago, and now you’re trying to pay that electric bill online. You’ve accessed your account with the utility company. And there it is, that blank box you’re supposed to fill in, right after the blank box that calls for your account number. It wants you to enter your bank’s routing number.
Not a problem. Banks' routing numbers aren't highly classified information. They're not confidential. Banks are more than glad to share theirs with you.
Open another tab in your browser and access your bank's website. The bank’s routing number should be posted somewhere on there, even if not clearly in neon. You can do the same type of search from your smartphone if you need the routing number when you’re on the go.
Sometimes you might have to hunt a little, however. For example, U.S. Bank’s website requires that you click on the “I’d like to…” tab on your transactions page to get the number. Wells Fargo Bank and Bank of America offer search tools on their website that let you find your branch location and the appropriate corresponding number. Many banks post their routing numbers on their “account information” or “account summary” pages.
Read More: Advantages and Disadvantages of Internet Banking
Checking the Good, Old-Fashioned Way
Another very easy way of tracking a routing number down is to simply call your bank and ask a customer service representative for it, but this carries a chance for error because mistakes might be made in the translation. You might think the representative said five when, in fact, they said nine. You might nonetheless take this route if you simply want to confirm a number you found on an unrelated website online. And yes, they’re out there, too. Some websites post routing numbers for all major banks.
And if you do happen to have paper checks on hand, the routing number will appear at the bottom of the check on the left side, next to your account number. It might not be labeled as "routing number," but remember, you’re looking for nine digits. You might simply see those nine digits, or the number might appear as 12 digits with the first three of them being zeroes.
Other Types of Routing Numbers
Unfortunately, you might encounter one more hiccup in the process of nailing down the correct routing number for your bank. Just as banking institutions have different numbers for each of their branches or locations – and some national banks have multitudes of branches – some also often have different numbers depending on the type of transaction you’re attempting to authorize.
This isn’t uncommon. Banks often do draw a line between wire transfers, ACH or automatic clearing house transfers and other types of payments. But the same routing number is ordinarily – although not always – used for electronic payments, direct deposits and paper checks. It’s usually just wire transfers that are set apart from the rest.
Read More: Can a Wire Transfer Bounce?
Finally, some entities that simply handle transactions for banks have their own numbers, too, but they’re not routing numbers. They’re referred to as “electronic transfer identifiers,” or ETIs. And ECIs, or traveler’s check identifiers, are used just by payers of traveler’s checks.
The one thing you can count on, however, is that no two banking institutions will share the same number.
- U.S. Bank: Find Your U.S. Bank Checking Account Routing Number
- OFX: What Is a Routing Number?
- Bank of America: How Do I Find My ABA Routing and Account Numbers?
- Bankrate: What Is a Routing Number on a Check and How Does It Work?
- American Bankers Association: Routing Number Policy and Procedures
- Bankrate: What Happens When You Write a Check?
- Office of the Comptroller of the Currency: Checking Accounts – Understanding Your Rights
- Wells Fargo: Routing Numbers and Account Numbers
- American Bankers Association. "ABA Routing Number." Accessed March 6, 2020.
Beverly Bird has been writing professionally for over 30 years. She is also a paralegal, specializing in areas of personal finance, bankruptcy and estate law. She writes as the tax expert for The Balance.