How long is an IBAN from Sao Tome and Principe?

25 characters, written in groups of four on paper (ST86 1234 5678 9012 3456 7890 1 as a synthetic example).

Can I find the bank from the IBAN?

The bank identifier is the 4 characters at positions 5–8; 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.

Sao Tome and Principe IBAN format

An IBAN from Sao Tome and Principe is 25 characters long: the country code ST, two check digits, then 8 digits (bank and branch code), 11 digits (account number), 2 digits (national part (check key or type)). Sao Tome and Principe is outside 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

25 characters in all. Registry notation of the BBAN: 8!n11!n2!n (n digits, a upper-case letters, c alphanumerics, ! fixed length).

Position	Length	Characters	Meaning
1–2	2	letters	country code ST
3–4	2	digits	check digits (ISO 7064 mod 97-10)
5–12	8	digits	bank and branch code
13–23	11	digits	account number
24–25	2	digits	national part (check key or type)

Example

ST86 1234 5678 9012 3456 7890 1 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

Sao Tome and Principe is outside the SEPA schemes: a transfer to this IBAN goes through correspondent banks, with fees on both sides and several days of delay. A payout system should warn before paying.

Check one

The API checks the characters, the country, the length (25), the mod-97 check digits and the BBAN pattern, and returns the bank and branch identifier.

curl — validate an IBAN from Sao Tome and Principe

curl "https://veriport.io/api/v1/iban/validate?iban=ST86123456789012345678901"

Questions

How long is an IBAN from Sao Tome and Principe?: 25 characters, written in groups of four on paper (ST86 1234 5678 9012 3456 7890 1 as a synthetic example).
Can I find the bank from the IBAN?: The bank identifier is the 4 characters at positions 5–8; 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.