IBAN Definition
An IBAN (International Bank Account Number) is a standardized way of writing a bank account number so it can be recognized in any country. It was introduced to reduce errors in cross-border payments and is defined by the ISO 13616 standard. Today 78 countries and territories use IBANs, including all of Europe, most of the Middle East, and parts of Latin America and Africa.
Notably, the United States, Canada, Australia, China, and India do not use IBANs for domestic accounts. Transfers to those countries use local formats (like US routing numbers) together with the bank's SWIFT code.
IBAN Structure
Take the German example DE89 3704 0044 0532 0130 00:
| Part | Example | Meaning |
|---|---|---|
| Country code (2 letters) | DE | Germany (ISO 3166-1) |
| Check digits (2 digits) | 89 | Mod-97 checksum over the whole IBAN |
| Bank code | 37040044 | The Bankleitzahl (German bank code) |
| Account number | 0532013000 | The domestic account number |
The part after the check digits varies by country: each country maps its existing domestic format into the IBAN, which is why lengths range from 15 characters (Norway) to 32 (Saint Lucia). See the full country format table.
How the Check Digits Work
The two check digits are computed with the ISO 7064 mod-97 algorithm: move the first four characters to the end, convert letters to numbers (A=10 ... Z=35), and divide the resulting large number by 97. A correct IBAN always leaves a remainder of exactly 1. Change any single character and the remainder changes, which is how a validator catches typos instantly, without contacting any bank.
IBAN vs SWIFT/BIC vs Routing Number
| Identifier | Identifies | Used in |
|---|---|---|
| IBAN | The specific account | 78 countries (Europe, Middle East, and more) |
| SWIFT / BIC | The bank (or branch) | Worldwide - verify one at SwiftCodeCheck |
| Routing number (ABA) | The bank, domestically | United States only |
Most international transfers into an IBAN country need both the IBAN (which account) and the SWIFT/BIC (which bank). Transfers to the US need a routing number and account number instead of an IBAN.
Is Sharing an IBAN Safe?
Yes. An IBAN alone lets people send money to your account, not take money out of it. It's printed on every invoice in Europe. That said, treat it like any personal data: combined with your name and other details it can be abused for social engineering, so share it with people you're actually transacting with.
Frequently Asked Questions
Does every country use IBANs?
No. 78 countries do, but the US, Canada, Australia, China, India, and others use local formats plus SWIFT codes instead.
Can a valid IBAN still be the wrong account?
Yes. The checksum catches typos, but a structurally valid IBAN can still belong to the wrong person. Always confirm the recipient's details before sending money.
Where do I find my own IBAN?
In your banking app or on your account statement. Many banks also print it on debit cards or show it in the account details screen.