What is an IBAN? A simple guide for US customers

If someone overseas has asked you for your IBAN — or you've been asked to provide one to receive a payment — you might be wondering what it actually is. Understanding IBANs is a great first step toward managing your global finances without the stress of traditional banking hurdles.

Read on to learn everything you need to know about IBANs and how they affect international money transfers. And, when you're done, explore how to send money abroad with Revolut.

What is an IBAN? The basics

An International Bank Account Number (IBAN) is a globally recognized system used to identify individual bank accounts across national borders. Originally developed by the European Committee for Banking Standards (ECBS) and later adopted as an international standard (ISO 13616), the IBAN was created to simplify the processing of international payments.

Before the IBAN system was introduced, different countries used different methods to identify bank accounts. This lack of consistency often led to errors, as banks struggled to correctly route money through unfamiliar systems. The IBAN has a standard format that helps banks check account details automatically. This makes it less likely that a transfer will be rejected or delayed.

When you send money to a country that uses the IBAN system, your bank uses this code to ensure the money reaches the correct financial institution and the specific account of your recipient. It's not a completely separate account number, but rather a different way of representing your existing bank details for international purposes.

How is an International Bank Account Number structured?

An IBAN can contain up to 34 alphanumeric characters. While the length varies depending on the country, the structure always follows a specific pattern to ensure accuracy. Every IBAN is divided into several distinct parts that convey essential information to the banks involved in a transfer.

Country code

The first 2 characters of an IBAN are always letters that represent the country where the account is held. For example, GB represents Great Britain, FR represents France, and DE represents Germany. This allows the sending bank to immediately identify the destination country.

Check digits

The country code is followed by 2 check digits. These numbers are calculated using a specific mathematical algorithm based on the rest of the IBAN. When you enter an IBAN into a payment system, the software uses these digits to verify that the entire code is valid. If a single character is mistyped, the check digits won't match, and the system will alert you to the error before the money is sent.

Basic Bank Account Number (BBAN)

The remaining characters are known as the Basic Bank Account Number (BBAN). The length and format of this section are determined by the individual country's central bank or payment authority. The BBAN typically includes:

• a bank identifier or code to specify the financial institution
• a branch code to identify the location where the account was opened
• the individual account number of the customer

By combining these elements into one string of characters, the IBAN provides all the routing information needed for a successful cross-border transaction.

Does the US use IBAN numbers?

It's a common source of confusion, but the US doesn't use IBANs for domestic banking. If you're sending money from one US bank account to another, you need a 9-digit ABA routing number and your standard account number.

Because the US banking system relies on its own established infrastructure, US-based accounts don't have their own IBANs. However, this doesn't mean that US customers can totally ignore the system. If you're a US resident sending money to Europe, the Middle East, or parts of the Caribbean, you'll almost certainly be asked to provide the recipient's IBAN.

And, if you're receiving a payment from a country that uses IBANs, the sender may ask for yours. Since US accounts don't have them, you should provide your SWIFT/BIC code and your domestic account details instead. Most international banks are equipped to handle transfers to the US using these alternative identifiers.

Learn more about receiving money from abroad.

Why do you need an IBAN for international transfers?

The main purpose of the IBAN system is to facilitate straight-through processing. This means the payment can be handled entirely by computers without the need for manual intervention by bank staff. This automation makes transfers faster and significantly more budget-friendly.

When you provide an accurate IBAN, you get the following benefits:

• Reduced errors: The check digits ensure that mistakes are caught right away.
• Faster delivery: Automated systems can route the money to the correct destination within seconds.
• Lower costs: Because less manual work is required, many banks can offer lower fees for IBAN-based transfers.

In many regions, such as the European Union, using an IBAN is mandatory for all electronic payments. Attempting to send money to these regions without one may result in the payment being returned to you, often with an additional failed payment fee deducted by the banks involved.

IBAN vs SWIFT and BIC: What's the difference?

When you start an international transfer, you'll often see the terms IBAN, SWIFT, and BIC used together. While they are related, they serve different functions in the global payment network.

SWIFT and BIC

The Society for Worldwide Interbank Financial Telecommunication (SWIFT) is a global messaging network that banks use to send and receive information about financial transactions securely. A Bank Identifier Code (BIC) is the unique address assigned to a specific bank on the SWIFT network.

Think of the SWIFT/BIC code as the address of the bank building itself. It tells the money which house to go to, but not which room to enter.

IBAN

The IBAN is the identifier for the specific account. If the SWIFT code is the bank's address, the IBAN is the specific mailbox for the customer inside that building.

In most cases, you'll need both to send money abroad. The SWIFT code gets the money to the right bank, and the IBAN ensures it's credited to the correct person.

How to find an IBAN number

If you're the one receiving money from an international sender, you'll need to find the IBAN for the account you wish to use. As we've mentioned, US accounts don't have IBANs, so this section only applies if you hold an account in a country that has IBANS, like a Revolut account in the UK or EEA.

You can typically find an IBAN in the following places:

• Your bank statement: Most banks print the IBAN and BIC clearly at the top of paper or PDF statements.
• Mobile banking app: In the Revolut app, you can find your account details by tapping on Details under your balance.
• Online banking: Log in to your provider's website and look for "Account Details" or "International Transfers".

If you're sending money to someone else, the safest way to get their IBAN is to ask them for it. While there are IBAN calculators available online, these tools can sometimes generate incorrect codes if the underlying bank data is out of date. Using an incorrect IBAN can lead to significant delays, so always double-check the number with the person you're paying.

What happens if you use the wrong IBAN?

The outcome of using an incorrect IBAN depends on whether the number you use is valid or not.

If you simply make a typo and the resulting code is mathematically impossible, the check digits will fail. Most fintech apps, including ours, will recognize this immediately and prevent you from sending the payment. This is the most common scenario and is easily fixed by double-checking the number.

If you enter a code that's valid but belongs to the wrong person, the situation is more difficult. Because wire transfers are often processed immediately, it can be very difficult to reverse a payment once it's been sent. In some cases, the bank may be able to contact the recipient to ask for the money back, but they can't force them to return it without a legal process.

Always double-check every digit before you confirm a transfer to make sure your money goes to the intended destination.

Sending money overseas with Revolut

We've built a platform that takes the guesswork out of international payments. Whether you're sending money to a friend in London or paying a supplier in Dubai, we help you navigate the requirements of the IBAN system with ease.

When you use Revolut for international transfers, you benefit from:

• competitive exchange rates: We provide access to great rates with no hidden charges.
• real-time tracking: You can see exactly where your money is and when it's expected to arrive.
• Built-in validation: Our app automatically checks IBANs for errors to help keep your money safe.

Our goal is to provide an experience that feels local, no matter where your money is going. By using local payment networks where possible, we often complete transfers faster than traditional banks that rely solely on old-school systems.

Learn more about our competitive rates for international transfers.

How to sign up for Revolut and start sending money

If you're ready to send your first international payment, joining the millions of customers who use Revolut is a straightforward process. Follow these steps to get started:

1. Download the app: Find the Revolut app on the Apple App Store or Google Play Store and download it to your device.
2. Create your account: Open the app and enter your phone number. You'll need to provide some basic information and verify your identity with a photo of a valid government-issued ID.
3. Add money to your account: Once your account is authorized, you can add money using a debit card, a transfer from a bank account, or through Apple Pay or Google Pay.
4. Initiate a transfer: Go to the Payments tab and tap the + symbol. Select International and choose the country you're sending to.
5. Enter recipient details: Enter the name and the IBAN of the person you're paying. We'll automatically verify the code to make sure it follows the correct format for that country.
6. Review and send: We'll show you the exchange rate, the fee, and the estimated arrival time upfront. Once you're happy with the details, tap Send and track your payment in real-time.

Exchange and global transfer fees, fair usage limits, and Terms and Conditions apply.