What is an IBAN?
An IBAN (International Bank Account Number) is a standard format for writing a bank account number so it can be used in cross-border payments: a two letter country code, two check digits and the national account number. Countries that adopt it register their format with Swift. Example (invented, for illustration only): GB52 EXMP 1234 5612 3456 78, a correctly formatted UK IBAN with GB as the country, 52 as the check digits, EXMP as the bank code, 123456 as the sort code and 12345678 as the account number.
- The IBAN is defined by ISO 13616, and ISO has designated Swift as the registration authority for national IBAN formats.
- An IBAN has a two letter country code, two check digits and up to 30 further characters, so it can run to a maximum of 34 characters.
- The check digits use the ISO/IEC 7064 MOD97-10 scheme, which catches most typing errors before a payment is sent.
- Swift's IBAN Registry, Release 103 of September 2026, lists the national formats, with fixed lengths such as 22 characters for Germany and the UK and 27 for France.
How an IBAN works
Every country has its own way of numbering bank accounts. The IBAN wraps the national number, called the BBAN (Basic Bank Account Number), in a common format so banks can process cross-border payments automatically. The standard is ISO 13616. Swift publishes the IBAN Registry, and only a national standards body or a national central bank can register its country's format.
The Registry describes the structure as a two letter ISO 3166 country code, followed by two check digits and up to thirty alphanumeric characters. The check digits are calculated with the ISO/IEC 7064 MOD97-10 scheme. Swift's registration rules state that account numbers issued by banks in countries outside the Registry cannot be called IBANs.
| Country | IBAN length | What the national part contains |
|---|---|---|
| Germany (DE) | 22 | 8 digit bank code, 10 digit account number |
| United Kingdom (GB) | 22 | 4 letter bank code, 6 digit sort code, 8 digit account number |
| France (FR) | 27 | Bank code, branch code, 11 character account number, 2 digit key |
| Spain (ES) | 24 | Bank, branch, check digits and 10 digit account number |
| Netherlands (NL) | 18 | 4 letter bank code, 10 digit account number |
| United Arab Emirates (AE) | 23 | 3 digit bank code, 16 digit account number |
| Brazil (BR) | 29 | Bank, branch, account number, account type and owner code |
| Pakistan (PK) | 24 | 4 letter bank code, 16 character account number |
Source: Swift, IBAN Registry, Release 103 (September 2026). As published on 29 October 2026.
Where a business meets an IBAN
A business meets the IBAN when it pays or is paid in euros, and when it pays a supplier in any country that has registered a format. For a SEPA payment in euros, the IBAN is the only account identifier the payer needs within the EEA. For a SWIFT wire, the IBAN goes in the account field and the bank's SWIFT code identifies the bank.
Not every country uses IBANs. The United States uses a routing number and an account number, Mexico uses the 18 digit CLABE, and India uses an account number with a branch code. Give a payer the format its own bank expects.
Common mistakes with IBANs
- Spaces and lowercase letters. IBANs are often printed in groups of four for reading, but the electronic form has no spaces. Most banks strip spaces; some systems reject them.
- Trusting the check digits too far. A valid IBAN only proves the number is well formed. It does not prove who owns the account. Since 9 October 2025, euro area payment providers must offer a check that the payee's name matches the IBAN.
- Assuming the IBAN shows the currency. An IBAN identifies an account, not a currency. Confirm the account receives the currency you send, or the receiving bank converts it.
- Inventing an IBAN for a country without one. If the supplier's country is not in the Registry, use its local account number and the bank's SWIFT code.
Related terms and how Helm handles it
The IBAN is the account identifier inside SEPA, the euro payments area, and works alongside the SWIFT code for international wires. In the UK, the IBAN contains the same sort code and account number that domestic Faster Payments use.
Helm provides EUR details with an IBAN in your company's own name, receiving SEPA and SWIFT payments, alongside USD and GBP details; see global accounts.
Open a Helm account
USD, EUR and GBP accounts in your company's name, with a named account manager.
Open accountQuestions
How long is an IBAN?
It depends on the country. The maximum is 34 characters, but each country has a fixed length: 22 for Germany and the UK, 27 for France and 18 for the Netherlands, according to Swift's IBAN Registry.
Does the US use IBAN numbers?
No. US bank accounts are identified by a nine digit ABA routing number and an account number. A payer abroad sending dollars to a US account uses the bank's SWIFT code and the account number.
Is an IBAN the same as a SWIFT code?
No. The IBAN identifies an account; the SWIFT code (BIC) identifies the bank. A cross-border wire often needs both.
How do I check an IBAN is valid?
The two check digits are calculated with the MOD97-10 scheme, so software can confirm the number is well formed. A valid format does not confirm the account holder's name, so confirm new details with the beneficiary.
Who issues IBAN formats?
Each country's national standards body or central bank registers its format with Swift, which ISO has designated as the registration authority for ISO 13616.
References
- Swift: IBAN, International Bank Account Number (ISO 13616)
- Swift: IBAN Registry, Release 103 (September 2026)
- Swift: IBAN registration procedures (ISO 13616)
- Deutsche Bundesbank: SEPA Credit Transfer
- Bird & Bird: Instant Payments Regulation (EU) 2024/886
This guide is general information for businesses, not financial, legal or tax advice. Rules, fees and timings were checked against the sources listed on the review date and may change.