An external account is any bank account you own somewhere other than the bank you're currently dealing with

When you open a new bank account or set up a transfer, your bank will ask whether you want to move money from an external account — meaning an account at a different bank, credit union, or financial institution. That's all the term means. It's not a special type of account. It's just their way of saying "money somewhere else."

You might have an external account because you bank at multiple places, because you switched banks and kept an old account open, or because you're moving money from a savings account at one bank to a checking account at another. Banks ask about external accounts because they need to know where the money is coming from or going to, and they need your permission to access it.

Key Takeaways

  • An external account is straightforward any bank account you own at a different financial institution than the one you're currently using.
  • Banks ask about external accounts when you set up transfers so they can move money safely and legally between institutions.
  • You'll need your routing number and account number from the external account to link it for transfers.
  • Linking an external account takes one to three business days, and the bank may send small test deposits to confirm you own it.
  • You can unlink an external account at any time through your online banking or by calling your bank.

Why banks ask about external accounts

Banks are required by law to know where money is coming from and going to. When you want to transfer funds between your account and an account at another institution, your bank needs written permission from you and confirmation that you actually own the external account. This protects you from fraud — if someone gains access to your account, they can't just drain it to a random account somewhere.

The other reason is practical: moving money between different banks takes time because the banks have to coordinate through a system called the Automated Clearing House, or ACH. Your bank needs to know the exact routing number and account number of the external account so the money goes to the right place. A single digit wrong, and the transfer either bounces back or goes to someone else's account.

How to link an external account to your bank

The process is straightforward. Log into your online banking, look for a section called "Transfer Money," "Link Account," or "External Accounts" — the exact name varies by bank. You'll be asked to enter the routing number and account number from the external account. The routing number is a nine-digit code that identifies the bank; the account number identifies your specific account at that bank. Both are printed on the bottom left of your checks, or you can call the other bank and ask.

After you enter this information, your bank will usually send two small deposits (often a few cents each) to the external account within one to three business days. You'll need to log into that external account, find those deposits, and report the exact amounts back to your original bank. This is called microdeposit verification, and it's how the bank confirms you actually own the external account and aren't trying to transfer money to someone else.

Once the bank confirms the amounts, the link is active and you can transfer money back and forth. The whole process usually takes three to five business days from start to finish.

What information you'll need

To link an external account, gather these details from the account you want to link:

  • The nine-digit routing number (identifies the bank)
  • Your account number at that bank
  • The type of account (checking or savings)
  • The name on the account (should match the name on your account at your current bank)

If you don't have checks from the external account, you can find the routing number on your bank's website or by calling the bank directly. Many banks also display it in their online banking system under account details.

How long transfers take

Once an external account is linked, transfers between your account and that external account usually take one to three business days. This is because the money moves through the ACH system, which processes transfers in batches overnight. If you transfer money on a Friday afternoon, it may not arrive until Tuesday, because the ACH doesn't process on weekends or federal holidays.

Some banks offer faster transfers called wire transfers, but these usually cost money (typically $15 to $30) and are meant for urgent, large transfers. For routine moving of money between your own accounts, the standard ACH transfer is free and fast enough for most situations.

Unlinking an external account

You can unlink an external account whenever you want through your online banking. Find the account in your transfer settings, look for a "Remove," "Unlink," or "Delete" option, and confirm. The account is then disconnected and you can no longer transfer to or from it. This doesn't affect the external account itself — it just breaks the link between your two banks.

If you can't find the option online, call your bank's customer service line and ask them to unlink the account for you. They can do it in a few minutes.

External accounts and account security

Linking an external account is safe as long as you're linking an account you actually own. The microdeposit verification step exists specifically to prevent someone from linking a stranger's account. However, once an external account is linked, anyone with access to your online banking can transfer money to it — so protect your login information the same way you would protect your debit card.

If you notice a transfer you didn't make, contact your bank when ready. Most banks have fraud protection that can reverse unauthorized transfers within a certain window, usually 60 days.

Frequently Asked Questions

Can I link an account at the same bank as an external account?

Most banks don't require you to link accounts at the same institution — you can usually transfer between your own accounts directly without the external account process. Check your online banking to see if there's a simpler transfer option for accounts at the same bank.

What if the microdeposit amounts don't show up in my external account?

Wait three to five business days from when you initiated the link. If the deposits still haven't arrived, contact your original bank and ask them to resend the microdeposits. If they arrive but you can't see them in your online banking, log out and back in, or call the external bank to confirm they posted.

Do I have to use my real name when linking an external account?

The name on the external account should match the name on your account at your current bank. If the names don't match, the bank may reject the link or flag it for review. If you've recently changed your name, update it at both banks before linking.

Can I link someone else's account as an external account?

No. The microdeposit verification step requires you to confirm the amounts, which means you need access to the external account. Linking someone else's account without their knowledge is fraud and is illegal.

What happens if I transfer money to the wrong external account by mistake?

Contact your bank when ready. If the transfer hasn't cleared yet, they may be able to stop it. If it has cleared, the bank can attempt to recover the funds, but there's no may provide. This is why it's important to double-check the account number before confirming a transfer.