Luxembourg IBAN format (LU) — length, structure, example

CountryLuxembourg (LU)
IBAN length20 characters
SEPA memberyes
Domestic check digit validatedno

Check a Luxembourg IBAN

Spaces and hyphens are fine — checked instantly as you type, only in your browser.

Luxembourg’s IBAN is a compact 20 characters, reflecting one of Europe’s densest banking sectors: a country of under 700,000 people hosting well over a hundred credit institutions, many of them branches of international groups.

Structure

The registry example LU28 0019 4006 4475 0000 (a published SWIFT test value, not a live account) reads:

Part Value Meaning
Country LU Luxembourg
IBAN check digits 28 standard modulo-97 pair
Bank code 001 Banque et Caisse d’Epargne de l’Etat, Luxembourg (Spuerkeess)
Account 9400644750000 13-character account identifier

The BBAN pattern is ^[0-9]{3}[A-Z0-9]{13}$: the bank code is always three digits, while the account part is alphanumeric — uppercase letters are permitted, although most institutions issue purely numeric accounts. There is no separate national check digit; integrity rests on the IBAN’s own modulo-97 pair.

Bank codes and the ABBL register

The 3-digit bank codes are assigned and published in the Luxembourg Register of IBAN and BIC codes, maintained by the ABBL (The Luxembourg Bankers’ Association) as the golden source for the country. The register maps each code to the institution’s name and BIC, from the low numbers of the long-established houses (001 Spuerkeess, 002 Banque Internationale à Luxembourg, 003 BGL BNP Paribas) up to 999 for the Banque Centrale du Luxembourg.

The validator above resolves the bank name and BIC from that register entirely in your browser; the IBAN never leaves your device.

SEPA and usage

Luxembourg is a founding euro-area member and fully inside SEPA, so an LU IBAN works for euro credit transfers and direct debits across the whole zone. Cross-border payments are the norm rather than the exception here — a large share of Luxembourg accounts are held by non-residents and funds, which is exactly the environment IBAN was designed for.

Frequently asked questions

How long is a Luxembourg IBAN?

A Luxembourg IBAN is 20 characters: LU, two IBAN check digits, a 3-digit bank code and a 13-character account identifier. The bank code is always numeric; the account part may contain letters as well as digits.

What does the 3-digit code after LU and the check digits mean?

Positions 5-7 identify the credit institution, using the code assigned in the Luxembourg Register of IBAN and BIC codes maintained by the ABBL, the Luxembourg Bankers' Association. For example 001 is Banque et Caisse d'Epargne de l'Etat, Luxembourg (Spuerkeess) and 999 is the Banque Centrale du Luxembourg.

Which bank does a Luxembourg IBAN belong to?

Read the three digits at positions 5-7 and look them up in the ABBL register, which maps each code to the institution's name and BIC. The validator on this page does that lookup for you locally in your browser — the IBAN itself is never sent anywhere.

Related: all country formats ·what is an IBAN

Data source: ISO 13616 IBAN Registry Release 102 (June 2026). Last verified: 2026-07-13.