IBAN (International Bank Account Number)

IBAN was developed by the European Committee for Banking Standards (later ECBS, then ISO 13616) to remove the operational risk of misrouted international payments caused by inconsistent national account-number formats. An IBAN encodes:

• Country code (2 letters, ISO 3166-1) — e.g., DE for Germany, ES for Spain, FR for France.

• Check digits (2 digits) — calculated using the MOD-97 algorithm; a wrong-digit IBAN typed by a payer will fail validation before the transfer is initiated.

• Basic Bank Account Number (BBAN, country-specific length) — the bank identifier (usually a national bank code) plus the customer's account number within the bank.

Lengths vary by country: Germany 22 chars, France 27, UK 22, Spain 24, Italy 27, Netherlands 18, Saudi Arabia 24, Brazil 29, etc. Maximum 34. The IBAN is paired with the BIC/SWIFT code (Bank Identifier Code) for international wires when SEPA isn't applicable.

IBAN-using countries in 2026 include: all EU/EEA member states, the UK, Switzerland, Türkiye, Israel, the Gulf states (UAE, Saudi Arabia, Bahrain, Kuwait, Qatar, Oman), Brazil, Egypt, Mauritania, Tunisia, Moldova, Ukraine, Belarus, parts of the Caribbean (St. Lucia, Dominican Republic), and several others. The OECD Better Money website maintains an updated list.

IBAN-NOT-using countries include: United States (uses ABA routing numbers + account numbers domestically; ACH internationally for SEPA-equivalent function but with very different fee and speed properties), Canada (institution-transit-account numbering), Mexico (CLABE — a similar standardised format but not technically IBAN), most of East Asia and Sub-Saharan Africa.

For expats:

• Receiving a SEPA transfer requires an IBAN — not a bank-name + account-number combination. Make sure your bank's IBAN is on file with payers.

• Sending money from a US dollar account to an IBAN destination is an international wire, not SEPA, and uses the IBAN + BIC + intermediary bank. Fees: $25-50 plus FX margin.

• Online tools like IBAN Calculator and the ECBS IBAN Registry validate IBAN format. Some banks also support IBAN-only validation (no BIC required) under SEPA.