Write your account number and routing number in the exact format your bank provides

When you give someone your bank account details—to set up direct deposit, receive a wire transfer, or authorize an automatic payment—you need to provide two pieces of information: your routing number and your account number. Write them exactly as they appear on your checks or in your online banking portal. Do not add dashes, spaces, or letters unless your bank specifically shows them that way. A single digit wrong will send money to the wrong account or cause the transaction to fail.

The routing number identifies which bank holds your account. Your account number identifies you within that bank. Together, they form the address where money should land. Most banks print both on the bottom left of your checks, but you can also find them by logging into your online account or calling customer service.

Key Takeaways

  • Your routing number and account number must be written exactly as your bank shows them, with no added punctuation unless the bank includes it.
  • The routing number appears first on checks (usually nine digits), followed by your account number (typically 10 to 12 digits).
  • If you are unsure of either number, log into your online banking account or call your bank rather than guessing.
  • Always double-check both numbers before submitting them, because a mistake will delay or misdirect the payment.

Where to find your routing and account numbers

On a paper check, look at the bottom left corner. You will see three groups of numbers separated by vertical lines. The first group (usually nine digits) is your routing number. The second group is your account number. The third group is the check number itself.

If you do not have checks or cannot read them clearly, log into your online banking account. Most banks display both numbers on the account summary or account details page. Some banks label them "Routing Number" and "Account Number." Others may call the routing number the "ABA Number" or "Transit Number." If you cannot find them online, call the customer service number on the back of your debit card or on your bank's website.

Do not rely on memory or old statements. Banks sometimes change routing numbers during mergers or reorganizations, and using an outdated number can cause the payment to fail or go to the wrong place.

The correct format for writing account details

Write your routing number first, then your account number, on separate lines or in the order the form requests. Use only the digits your bank provides. If your bank shows your routing number as "021000021," write it exactly that way—not "021-000-021" or "021 000 021" unless the form specifically has boxes or dashes for you to fill in.

Some forms ask for the information in a specific order or layout. Follow that layout exactly. If a form has separate boxes for each digit, fill each box with one number. If it has a single line, write both numbers with a space between them or on separate lines, depending on what the form shows.

Never add letters, dashes, or punctuation that your bank does not show. Leading zeros matter—if your routing number starts with zero, include it. A missing zero will route the payment to a different bank entirely.

What information to include and what to leave out

You need only your routing number and account number. Do not write your full name, address, or phone number unless the form specifically asks for them. Do not include your PIN, password, or the three-digit security code from the back of your debit card. Those are for you alone and should never be shared.

If someone asks for your Social Security number along with your account details, that is normal for wire transfers, ACH payments, and direct deposit setup—those transactions require identity verification. But verify that you are dealing with your actual bank or a legitimate payroll system before you provide it. Scammers sometimes pose as banks to collect this information.

Common mistakes that delay or block payments

Transposing digits is the most common error. A single number out of place will cause the payment to fail or go to another account at your bank. Always read your account details aloud to yourself or to the person taking them, then read them a second time to catch mistakes.

Using an old routing number is another frequent problem. If your bank merged with another bank or changed its name in the last few years, the routing number may have changed. Check your most recent statement or log into your account to confirm you have the current number.

Adding formatting that is not on your bank statement also causes rejections. If you see "021-000-021" on a form but your bank shows "021000021," use the version without dashes. The system reading the form is looking for exact matches.

Providing account details safely

Only give your routing and account number to people and organizations you trust. Your employer needs them for direct deposit. Your utility company needs them to set up automatic bill pay. Your bank needs them to process transfers. But a stranger who calls or emails asking for this information is likely running a scam.

If you are setting up a payment online, make sure the website is secure. Look for "https://" at the start of the web address and a padlock icon in the browser. Never paste your account details into an email or text message. If a company asks you to email your banking information, call them back using the phone number on their official website to verify they actually need it.

If you have already given your account details to someone you now suspect was fraudulent, contact your bank immediately. Most banks can monitor your account for unauthorized activity and may be able to reverse fraudulent transactions if you report them quickly.

What happens after you submit your account details

For direct deposit and automatic bill pay, your bank will verify the routing and account number. If either is wrong, the setup will fail and you will get an error message. Go back and check both numbers against your bank statement or online account, then try again.

For wire transfers and ACH payments, the money usually moves within one to three business days. If the account number is wrong, the receiving bank will reject the transfer and send it back to your bank. This can take five to ten business days, and you may see a temporary debit and credit on your account as the money bounces back.

If money goes to the wrong account because of an error on your part, contact your bank immediately. They can attempt to recover the funds, but success depends on whether the receiving bank cooperates. It is not may provide, which is why double-checking before you submit is critical.

Frequently Asked Questions

Can I use my account number without the routing number?

No. Your account number alone does not tell the system which bank to send the money to. You need both the routing number and the account number. Some forms ask for them separately; others ask for them together. Either way, both are required.

What if my bank has multiple routing numbers?

Large banks sometimes have different routing numbers for different regions or transaction types. Use the routing number that corresponds to the branch where your account is held. Your checks will show the correct one. If you are unsure, call your bank or check your online account details.

Is it safe to write my account details on a check?

Yes. Checks are designed to show your routing and account number. Anyone who receives a check can see this information, and that is normal. However, do not write your account details on a piece of paper and leave it lying around, and do not email or text them to someone unless you initiated the request.

What should I do if I made a mistake when giving my account details?

Contact the organization that received them immediately. If it is your employer or a company you trust, explain the error and provide the correct information. If the payment has not yet been processed, they can usually update it. If it has already gone through, contact your bank to see if the transaction can be reversed or recovered.

Do I need to provide account details for online shopping or credit card payments?

No. For online shopping, you provide a credit or debit card number, not your bank account details. Your bank account number is only for direct transfers from your bank account—direct deposit, bill pay, wire transfers, and ACH payments. Never give your account number to a retail website.