Underpaid tax filling

Hello! I moved to the UK in the end of 2022. In September 2023 I received P800 form that I underpaid £460.80 tax for company benefits in the year ending in 2023. I opted in for taking that money from future taxes. In the 2023-2024 year I had tax code 0T. In current tax year I have tax code starting from K with an explanation of underpaid 460.80 pounds. I now fill in self-assessment form for 2023-2024 and stuck in the "underpaid tax included in PAYE" coding. Should I put "0" in the "amount of underpaid tax for earlier years included in your tax code for 2023-24" since PAYE code is equal to 0T? Or should I put 460.80 here because of P800?

Hi

While it's probable that you would put 0.00 in this 23/24 box, as your 22/23 underpayment is being paid through your 24/25 tax code, we may need to review your codes and calculations to confirm this.
Contact us by webchat or phone via Self Assessment: general enquiries to allow us to do this.

Thank you