An IBAN (International Bank Account Number) is a number used to identify bank accounts across national borders.
The UK IBAN consists of 22 characters: 2 letter country code; 2 digits check number; 4 characters from the bank's bank code; 6 digits sort code for the bank branch and 8 digits code for the bank account number.
A SWIFT code (or BIC number) is a standard format of a 'Business Identifier Code'. It is a unique identification code for each bank, which is used when transferring money between banks internationally and can usually be found on your online or paper statement; if you are unsure, please contact your bank.
The standard format is 8 or 11 characters, 4 letters: Institution Code or bank code, 2 letters: Country Code, 2 letters or digits: location code and 3 letters or digits (optional): branch code.