SEPA coverage · 🇬🇧 GB

Convert United Kingdom IBANs to their BIC

Every United Kingdom IBAN is 22 characters long and starts with GB. The bank identifier embedded inside it is what resolves to a BIC/SWIFT code, the bank's name and address, and its SEPA reachability.

22
IBAN length
characters, fixed
GB
Country code
ISO 3166-1
GBP
Currency
SEPA payments settle in EUR
18
Structure
BBAN characters after the check digits

The United Kingdom IBAN format

Example of a valid United Kingdom IBAN:

GB29 NWBK 6016 1331 9268 19

Structure of a United Kingdom IBAN, segment by segment
Segment Length Example Meaning
Country code2GBAlways GB
Check digits229ISO 7064 mod-97 checksum over the whole IBAN
Bank code (BIC prefix)4NWBKFirst four letters of the bank’s BIC
Sort code6601613Numeric code identifying the branch
Account number831926819Numeric account identifier

The UK remained a SEPA participant after Brexit, so GB IBANs are still reachable for SEPA euro transfers — though intermediary fees may apply and address details are now often required.

How to get the BIC from a United Kingdom IBAN

01

Validate the IBAN

Check the length (exactly 22 characters for GB) and the ISO 7064 mod-97 checksum. Both are local computations — no lookup needed yet.

02

Extract the bank identifier

The bank code (bic prefix) (4 characters) inside the BBAN identifies the institution holding the account.

03

Resolve it to a BIC

Map the bank identifier to the institution's BIC via registry data — or send the IBAN to the API and get BIC, bank details and SEPA flags in one response.

Resolve it with one API call

Send the IBAN to POST /v1/convert and get back the BIC, bank details and the four SEPA reachability flags. Invalid and not-found lookups are always free.

curl https://api.iban2bic.com/v1/convert \
  -H "Authorization: Bearer ibk_live_xxx" \
  -H "Content-Type: application/json" \
  -d '{ "iban": "GB29NWBK60161331926819" }'

United Kingdom IBAN — frequently asked

Other SEPA countries

Keep reading

Resolve United Kingdom IBANs programmatically

BIC, bank details and SEPA reachability for any GB IBAN — €0.009 per successful call, failures always free.