UK Interest 02 - Untaxed UK interest etc (amounts that have not been taxed at all)
If you have an account that pays you gross interest for example a bank or building society account, enter the amount in this box.
If you think the information you are adding has an effect on your 6 April 2020 to 5 April 2021 or 6 April 2021 to 5 April 2022 PAYE Tax codes there is guidance to tell you how to let HMRC know of the change - If you think your code is wrong.