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United Kingdom IBAN Generator

Free test GB IBANs: 22 characters, official registry format, valid check digits.

United Kingdom IBAN generator

22-character format, official registry structure.

Same country + seed + row order gives the same test values. Leave blank for random samples. Seed algorithm: v1. Do not enter personal data.

United Kingdom IBAN format

A United Kingdom IBAN is 22 characters long: the GB country code, 2 check digits, and a 18-character BBAN (4 letters + 6 digits + 8 digits). Here is how a generated test IBAN breaks down:

PartExampleFormat
Country codeGB2 letters (ISO 3166)
Check digits472 digits: mod-97 checksum
Bank codeZZOZ4 letters
Branch code3046146 digits
Account number711753328 digits

Full test IBAN: GB47 ZZOZ 3046 1471 1753 32 (random test value)

About United Kingdom IBANs

  • The UK BBAN uses a 4-letter bank code, a 6-digit sort code (the branch identifier, written XX-XX-XX), and an 8-digit account number.
  • UK IBANs are 22 characters: the same length as Germany's, but with a completely different internal layout.
  • Sort codes have no public checksum; the authoritative list is maintained by the UK banking industry.

Use test United Kingdom IBANs for

  • Testing payment forms that accept United Kingdom bank details.
  • QA fixtures and demo data with the correct 22-character structure.
  • Validating your own mod-97 implementation against known-correct outputs.

Country-specific testing notes

The four bank letters, six sort-code digits and eight account digits are separate components. UK modulus-checking exceptions and active sort-code directory checks are outside this tool.

Test more than the happy path

Generate with seed country-regression-v1, preserve the selected country and quantity, then run again to reproduce the same rows. Include an invalid-checksum input and a shorter input in your form tests. The versioned fixture pack supplies expected results for the implemented format checks.

Interpret the result correctly

Our checks cover the registered length, character pattern and international check digits. They do not certify domestic checksums, reserved-value rules, active bank codes, account existence or recipient ownership. Use bank-issued details for payments and your provider’s documented sandbox values for integration tests.

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Frequently asked questions

22 characters: GB + 2 check digits + 4-letter bank code + 6-digit sort code + 8-digit account number.
A 6-digit number identifying the specific UK bank branch holding the account. Generate test ones on our sort code generator page.
They are synthetic test values with valid structure and check digits. This site does not query live bank directories, so generated values are not guaranteed to be unassigned.
Yes: paste any United Kingdom IBAN into our IBAN validator to check its length, structure and mod-97 checksum.
Testing and educational use. Generated identifiers are synthetic and are not checked against live bank directories. A randomly generated value can coincidentally resemble or match a real identifier. Never use generated data for real payments, account applications, identity verification, or to represent a real person or institution.