Reporting Savings Interest

Would you please clarify when interest on multi-year fixed term savings accounts needs to reported to HMRC, as there appears to be a grey area that causes a lot of confusion. The confusion arises when an account has multiple options to where annual interest can be credited. Option 1 allows the interest to be credited to a different account from where it can be accessed immediately. (By taking this option it is obvious that the the interest needs to be reported to HMRC in the tax year that it is received). Option 2 allows the interest to be credited back to the original account where it cannot be accessed until the account matures. In this situation does the interest need to be declared in the tax year when it is credited to the account, or at the end of the fixed term? The grey area appears to be that the interest was available to be accessed, but it was an individual choice to have it credited back into the fixed term account. I have looked through the HMRC website but cannot find a definitive answer to this question.

Hi,
This depends on the savings account and when you can access it. If you have to wait until the end of the fixed term before being able to access the capital and interest, the interest is reported in the tax year when the at the end of the term. If you can access the interest and capital at anytime, then you report the interest in each tax year.
Thank you

That is interesting because my wife has an account with Vanquish Bank where the interest could be withdrawn or credited back into the account, she decided to have it paid back into the account. So according to your reply the interest will not be reportable to HMRC until tax year 2025/26 when the account matures. However, Vanquish Bank have said that they will be reporting this interest to HMRC in the current tax year 2024/25, and it is my understanding that HMRC go by the figures reported to them by the financial institutions.