The three numbers on your check and what they do

Every check has three sets of numbers printed at the bottom. From left to right, they are: your routing number, your account number, and your check number. The routing number tells the banking system which bank holds your account. The account number identifies which specific account at that bank the money should come from. The check number is just for your own record-keeping — it doesn't affect how the check moves through the system.

These numbers are printed in a special machine-readable format called MICR (Magnetic Ink Character Recognition). The numbers look slightly different from regular printed text because they're designed to be read by the sorting machines banks use to process thousands of checks per day.

You'll use the routing and account numbers whenever you set up direct deposit, arrange automatic bill payments, or give someone your banking information to deposit a check electronically. The check number is just for you — write it in your checkbook register so you can track which checks you've written.

Key Takeaways

  • Your routing number is the nine-digit code on the far left of the bottom line, and it identifies your specific bank or credit union.
  • Your account number comes next and is usually 10 to 12 digits long, identifying your individual account within that bank.
  • The check number appears on the far right of the bottom line and also in the top right corner of the check itself.
  • You need both the routing number and account number together whenever you provide banking information to an employer, utility company, or other organization.

Finding your routing number at the bottom of the check

Look at the bottom left corner of your check. The first set of numbers you see — always nine digits long — is your routing number. It will be enclosed in special symbols that look like colons or dashes on both sides (they're called MICR symbols). This number is the same on every check from your account.

The routing number is specific to your bank or credit union and the location where your account was opened. If you have accounts at two different banks, each will have a different routing number. If you move to a different branch of the same bank, your routing number usually stays the same.

You can also find your routing number on your bank's website, by calling the customer service number on the back of your debit card, or by logging into your online banking. But the fastest way is straightforward to look at any check you have on hand.

Finding your account number next to the routing number

when ready to the right of your routing number is your account number. This is usually 10 to 12 digits long, though the exact length varies by bank. Like the routing number, it's printed in the special MICR format and enclosed in those symbol markers.

Your account number is unique to you — no one else at your bank has this number. This is what distinguishes your account from every other account at the same bank. If you have multiple accounts at the same bank (a checking account and a savings account, for example), each one has its own account number, but they share the same routing number.

When you write down your account number to give to someone, make sure you copy all the digits. A single wrong digit will send the money to the wrong account or cause the transaction to be rejected.

Why the order matters when you write them down

When you need to provide your banking information — to set up direct deposit at a new job, for instance — you'll always write the routing number first, then the account number. This is the standard order across all U.S. banks and financial institutions. If you reverse them, the transaction will fail.

Some forms will have separate boxes labeled "Routing Number" and "Account Number," which makes it obvious where each goes. Other forms might just say "Bank Information" and expect you to know the order. When in doubt, write the routing number first.

If you're filling out a form online, the system usually won't let you submit it if the numbers are in the wrong order or if you've entered the wrong number of digits. But with paper forms, it's up to you to get it right the first time.

The check number and why it's separate

The check number appears twice on your check: once at the bottom right in the MICR line, and once in large print in the top right corner. This number is unique to that individual check — the next check in your book will have a different number.

The check number is for your personal tracking only. When you write a check, you write the check number in your checkbook register along with the date, who you paid, and the amount. This helps you keep track of which checks you've written and when. The check number does not affect how the check is processed by the bank.

If you lose a check or decide not to use it, the check number straightforward goes unused. You don't need to tell your bank about it. The routing and account numbers are what the banking system uses; the check number is just your organizational tool.

What to do if you can't read the numbers clearly

If the numbers on your check are faded, smudged, or hard to read, don't guess. Call your bank's customer service number (on the back of your debit card or on your bank's website) and ask them to read the numbers to you over the phone. They can verify both your routing number and account number in seconds.

You can also log into your online banking account if you have one set up. Most banks display your routing number and account number in the account details or settings section. This is often the fastest way to find the information without making a phone call.

Never write down numbers you're unsure about. A single digit wrong will cause direct deposit to fail, bill payments to go to the wrong place, or checks to bounce. Taking 30 seconds to verify is worth it.

Frequently Asked Questions

Is it safe to give someone my routing and account number?

Your routing number is public information — it's printed on every check you write and is the same for all customers at your bank. Your account number is more sensitive. You should only give both numbers together to people and organizations you trust, like your employer, your bank, or a utility company you're paying. Never share them in response to an unsolicited email or phone call.

Do I need both numbers, or just one?

You need both together. The routing number tells the system which bank, and the account number tells it which account at that bank. Without both, the transaction cannot be processed. If someone asks for just one, they probably don't know what they're doing — ask them to clarify what they need.

Will my routing and account number change if I move or switch banks?

If you stay with the same bank but move to a different branch, your numbers usually stay the same. If you open an account at a different bank, you'll get a new routing number and a new account number. If you open a second account at the same bank, you'll get a new account number but keep the same routing number.

What if I write down the numbers wrong?

If you give someone the wrong routing or account number, the transaction will either be rejected or sent to the wrong account. If money goes to the wrong account, contact your bank when ready and explain what happened. They can often recover the funds, but it takes time. Always double-check before you hand over the information.

Can someone use my routing number alone to take money from my account?

No. Your routing number alone is not enough to access your account — they would also need your account number. Even with both numbers, they cannot withdraw money without your authorization. Your bank protects against unauthorized transactions through other security measures. If you're concerned about fraud, contact your bank directly.