What Is a Routing Number? Definition and Where to Find Yours

You’ve seen them in relation to your bank account, and shared them with your employers when setting up direct deposit for your paycheck. They’re routing numbers: that string of digits in the bottom left corner of your check.

What is a routing number?

Routing numbers are nine-digit numbers that identify your bank or credit union in a financial transaction. The numbers were adopted by the banking industry in 1910 to make transactions quicker and more efficient. With each bank having one specific number assigned to it, the chances of miscommunication are reduced. So even if two banks have similar names, they’re clearly distinct from one another because of their different routing numbers.

Skip to routing numbers at the three largest banks:

• Bank of America routing numbers

• Chase routing numbers

• Wells Fargo routing numbers

When you’ll need your routing number

You’ll need your routing number in a variety of situations, including setting up direct deposit, automatic loan payments or recurring transfers like bill payments.

You’ll also need it when you file taxes to receive your tax refund or debit a tax payment, or when you conduct Automated Clearing House, or ACH, transfers between accounts at different banks.

You will only need your routing number when funds are being directly transferred to or from your bank account — never for debit card or credit card purchases.

How to find your routing number

You can find your routing number at the bottom left corner of your personal checks. It’s the first nine digits of the long line of numbers there. Called the magnetic ink character recognition line, that string of numbers contains your routing number, account number and the check number, listed in that order.

If you don’t have a check handy, you can also find your routing number in the following places:

• Your bank statement

• Your bank’s website or mobile app

• Through your bank’s phone customer service

• The American Bankers Association’s routing number lookup

Be aware that routing numbers can change. Financial institutions can close branches, reorganize their operations or change the purpose of a routing number, all of which can affect the number connected to your account. Confirm your routing number with your bank before using it to avoid giving out the wrong number.

» Paying by check for the first time? Learn how to write a check correctly

Each bank has at least one routing number, although larger banks can have more. At a bank with multiple routing numbers, they can change depending on the location where you opened your account and the type of transaction you’re making.

If you live in Texas, for example, your routing number to set up direct deposit can be different from your friend’s in California, and different from your mom’s when she’s accepting an incoming wire transfer — even if the three of you use the same bank.

Bank of America routing numbers

Confirm that your state's routing number below is the same on your checks or logged-in online account.

Disclaimer: These are Bank of America routing numbers for checking accounts for electronic payments only. Some states or regions have different routing numbers for checks and electronic payments. In most cases, there are separate routing numbers for wire transfers as well.

Chase routing numbers

Confirm that your state's routing number below is the same on your checks or logged-in online account.

Disclaimer: These are Chase routing numbers by state for business accounts. NerdWallet independently confirmed that California's personal and business routing numbers are identical but could not confirm all routing numbers for personal accounts by state.

Wells Fargo routing numbers

Confirm that your state's routing number below is the same on your checks or logged-in online account.

Disclaimer: These are Wells Fargo routing numbers for checking accounts that aren't used for wire transfers. There are two for California, but the one listed below works across the state.