United Kingdom IBAN calculator and checker

A UK IBAN has 22 characters: GB, two check digits, then the bank identifier (first 4 letters of the BIC), sort code and account number. Enter the local details to build one, or paste an IBAN to check it, all in your browser.

Calculate or check a UK IBAN

Enter the bank identifier (first 4 letters of the BIC), sort code and account number. The calculator pads short numbers with zeros, works out any national check digits you leave empty and adds the two IBAN check digits.

Switch to Check to paste an IBAN instead: it tests the length, characters, check digits and national check, and shows the bank, branch and account parts. Nothing you type leaves the page.

GB IBAN format

A UK IBAN is 22 characters: GB, two check digits, then the bank identifier (first 4 letters of the BIC), sort code and account number.

In the printed format, k marks the check digits, a and b the bank, s the branch, sort code or prefix, c the account number and x a national check character.

IBAN length
22 characters
Check digits
2 digits after GB
Bank identifier (first 4 letters of the BIC)
4 letters
Sort code
6 digits
Account number
8 digits
National check digit
None
SEPA
Yes, outside the EEA
Printed format
GBkk bbbb ssss sscc cccc cc
Example IBAN
GB29 NWBK 6016 1331 9268 19

IBAN calculators for UK banks

Frequently asked questions

  • 22 characters: GB, two check digits, then the bank identifier (first 4 letters of the BIC), sort code and account number. Printed in groups of four, it looks like GB29 NWBK 6016 1331 9268 19.

  • Take your bank’s four-letter code (the first four letters of its BIC, such as NWBK for NatWest), then the six-digit sort code and the eight-digit account number, and add GB and two check digits: GB29 NWBK 6016 1331 9268 19. Your bank’s app or statement shows the IBAN as well.

  • Yes. The United Kingdom stayed in SEPA’s geographical scope after Brexit, from 1 February 2020, by an EPC decision of 7 March 2019. Guernsey, Jersey and the Isle of Man use GB IBANs and are in SEPA too. Euro payments to a UK IBAN can go by SEPA credit transfer when the receiving bank takes part in the SEPA schemes. SEPA covers euro payments only, so a payment in pound sterling goes outside it.

  • With the ISO 7064 mod 97-10 algorithm. The bank identifier (first 4 letters of the BIC), sort code and account number and the country code GB are turned into digits, and the two check digits are chosen so the whole number leaves a remainder of 1 when divided by 97. The calculator does this for you and rejects any input that cannot make a valid GB IBAN.

  • Yes. The calculator and the checker run entirely in your browser: the details you enter are never sent to a server, stored or shared. There is no sign-up and no fee.

  • Yes. The calculator covers 41 countries and the checker all 89 in the SWIFT IBAN registry. Pick a different country in the form above, or open its page from the list below.

Paying an IBAN from stablecoins? Holyheld Business converts USDC to EUR and pays it out by SEPA. See pricing or the guide to off-ramping USDC to an IBAN.

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