How long is an IBAN from Greece?

27 characters, written in groups of four on paper (GR39 1234 5678 9012 3456 7890 123 as a synthetic example).

Can I find the bank from the IBAN?

The bank identifier is the 3 characters at positions 5–7; the bank’s name and BIC are in SWIFT’s licensed directory, which the API does not resolve.

Does a valid IBAN mean the account exists?

No. The check digits and the structure say the IBAN is well formed; existence and ownership are known to the bank only, at payment time.

Greece IBAN format

An IBAN from Greece is 27 characters long: the country code GR, two check digits, then 3 digits (bank code), 4 digits (branch code), 16 alphanumeric characters (account number). Greece is in SEPA. Length and structure from the SWIFT IBAN Registry (ISO 13616), transcribed 2026-10-24; the SEPA flag from the EPC list.

Published 2026-10-28

Structure

27 characters in all. Registry notation of the BBAN: 3!n4!n16!c (n digits, a upper-case letters, c alphanumerics, ! fixed length).

Position	Length	Characters	Meaning
1–2	2	letters	country code GR
3–4	2	digits	check digits (ISO 7064 mod 97-10)
5–7	3	digits	bank code
8–11	4	digits	branch code
12–27	16	alphanumeric characters	account number

Example

GR39 1234 5678 9012 3456 7890 123 is a synthetic example: placeholder characters in every part, with the check digits computed so that the mod-97 test passes. It is not a real account and no bank issued it; use it to test an input field, not to pay.

SEPA

Greece is in the geographical scope of the SEPA schemes: a euro credit transfer to this IBAN costs the same as a domestic one and arrives within one business day (seconds with SCT Inst).

Check one

The API checks the characters, the country, the length (27), the mod-97 check digits and the BBAN pattern, and returns the bank and branch identifier.

curl — validate an IBAN from Greece

curl "https://veriport.io/api/v1/iban/validate?iban=GR3912345678901234567890123"

Questions

How long is an IBAN from Greece?: 27 characters, written in groups of four on paper (GR39 1234 5678 9012 3456 7890 123 as a synthetic example).
Can I find the bank from the IBAN?: The bank identifier is the 3 characters at positions 5–7; the bank’s name and BIC are in SWIFT’s licensed directory, which the API does not resolve.
Does a valid IBAN mean the account exists?: No. The check digits and the structure say the IBAN is well formed; existence and ownership are known to the bank only, at payment time.

Free: five checks, bank identifier, SEPA flag.

Check an IBAN

Sources

IBAN Registry (ISO 13616) — country lengths, BBAN structures, SEPA membership — SWIFT, ISO 13616 registration authority, consulted 2026-10-24. Transcribed from the public registry; the release number in force on the day checkout opens must be written on the IBAN docs page (owner step).
ISO 13616-1:2020 — Financial services — International bank account number (IBAN): structure and mod 97-10 check (ISO/IEC 7064) — ISO, consulted 2026-10-24
EPC list of SEPA scheme countries (geographical scope of the SEPA schemes) — European Payments Council, consulted 2026-10-24. The 2025 additions (Albania, Moldova, Montenegro, North Macedonia, effective 5 October 2025) are flagged `sepaSince` on the row.