IBAN length is not universal: it ranges from 15 characters (Norway) to 33 (Russia). Each of the 89 IBAN countries defines its own exact length, because each wrapped its existing national account format in the IBAN envelope instead of redesigning it. Get the length wrong by even one character and the IBAN is invalid.
Common IBAN lengths
| Length | Countries |
|---|---|
| 15 | Norway |
| 16 | Belgium |
| 18 | Netherlands, Denmark, Finland, Faroe Islands, Greenland, Falkland Islands, Sudan |
| 20 | Austria, Lithuania, Luxembourg, Kazakhstan, Mongolia, Kosovo |
| 21 | Switzerland, Liechtenstein, Latvia |
| 22 | Germany, UK, Ireland, Spain, Croatia, Serbia, Montenegro, Vatican City |
| 23 | UAE, Israel, Iraq, Gibraltar, Oman, Somalia |
| 24 | Spain, Saudi Arabia, Czechia, Slovakia, Romania, Tunisia, Moldova |
Full authoritative table: see IBAN format by country for all 89 with exact BBAN structures.
Why it matters for validation
Length is the first and cheapest validation check: if the IBAN is not exactly the country's registered length, it is rejected before any checksum math runs. Our IBAN validator checks length automatically against the registry.
Why lengths differ so much
Legacy. Belgium's compact 12-digit national number yields a 16-character IBAN; Brazil's bank+branch+account+type encoding needs 29; Russia's 33-character format is the longest registered. The IBAN standard (ISO 13616) allows up to 34 characters total: no country currently uses the maximum.
Count the electronic value
Length refers to the complete compact IBAN, including the two country letters and two international check digits. Do not count printed spaces. The German example DE89 3704 0044 0532 0130 00 contains 22 characters, despite occupying more positions when displayed with spaces.
Use the country prefix before checking length
Different countries can share a length while using different national layouts. Germany and the United Kingdom both use 22 characters, but the UK format contains bank letters. Length alone cannot decide which national pattern applies or whether the check digits are consistent.
| Example country | Total characters | BBAN characters |
|---|---|---|
| Germany | 22 | 18 |
| United Kingdom | 22 | 18 |
| France | 27 | 23 |
| Spain | 24 | 20 |
| Netherlands | 18 | 14 |
| Norway | 15 | 11 |
Do not shorten an identifier to fit a field
If a payment form rejects a longer value, check whether it is requesting a domestic account number instead of an IBAN. Removing a country prefix, leading zeroes or a final group to fit the field changes the data. Confirm the requested identifier with the receiving bank or service.
For software: separate limits from validation
A field may allow the general maximum IBAN length, while validation still applies the exact length for the selected country. A generous input limit is not permission to accept every value below that limit. Keep supported-country data versioned and test shorter, longer and alphanumeric layouts.
This reference represents the formats supported by the toolkit’s bundled data. It is not a list of countries supported by every payment provider. Swift maintains the national format registry; a provider can support a smaller set or impose additional rules.
Sources and scope
Swift: national IBAN formats and registration authority.
Examples and test matrices are explanatory fixtures, not receiving instructions. This page covers format checks and software testing. It does not verify account ownership or provide a guarantee that a payment will succeed.
Technical notes updated 8 October 2026. Read the editorial policy. Send a correction.