The next 2 characters ("KK") specify the check digits, used to confirm integrity of the code. Only digits. The remaining characters ("BBBBBBBBBBBB") specify the Basic Bank Account Number (“BBAN”). The format is decided by the national central bank or designated payment authority of each country. Both letters & digits are allowed.
AA: Country code: the country that the bank account is held in. BB: Check digits: enable the sending bank to perform a security check of the routing destination. CCCC: Bank identifier: This code identifies the account holder’s bank. DDDDDD: Sort code. EEEEEEEE: Account number. How to find your account number within your IBAN
The sort code is a 6 numeric digit number that identifies the UK institution and branch. The sort codes are registered by BPSL. For the purposes of the BBAN, the sort code is not depicted as three two digit numbers separated by hyphens. The account number is an 8 numeric digit number that identifies the individual customer’s clearing account Find an account number using an IBAN. Because your IBAN displays your country codes, your sort code and account number, you can use it to pinpoint the address of your bank branch. The country code identifies the country of the banking institution, and each individual branch has its own sort code.
[CCCC] bank identifier: this code identifies the account holder’s bank [DDDDDD] sort code [EEEEEEEE] account number. Once you have found an IBAN number, it is easy to identify an account number: they are the last 8 - 12 digits of your IBAN. Using the previous example, the account number would be [EEEEEEEE].
ROI Customers. This IBAN calculator is provided to assist customers generate their IBAN numbers and is based on correct input of both the National Sort Code and bank account details. If incorrect details are supplied, the calculator will generate an incorrect IBAN. Customers must ensure the details entered are correct and use this IBAN . 162 337 339 396 326 22 275 96 168

how to get account number and sort code from iban