Doug Hughes

I have the same issue. My P800 says I have underpaid for 2022-23, and I agree. But when I logon to my personal tax account it says I have paid the correct amount. Moreover, contrary to the comment by HMRC Admin 25 above, when I check the tax for 2022-23 I see the message "Based on the information that HMRC have, £xxx was the right amount of Income Tax for you to pay.", where xxx is the amount of tax I actually paid, but less than the amount I should have paid. If I have to make payment by cheque in the post, what is the latest date for doing this before my 2024-25 tax code is changed to reclaim the underpayment?

In August 2023 I received a P800 message saying that I have underpaid income tax for the 2022-23 year, which is correct. However, when I logon to my personal tax account online, I see a box with "You paid the right amount of Income Tax for 6 April 2022 to 5 April 2023". And there doesn't appear to be any way to pay the amount I owe online. How can I pay this outstanding amount? I would rather pay the amount as a lump sum than an adjustment to my 2024-25 tax code. What is the latest date I can pay the amount before my 2024-25 tax code is adjusted? Many thanks.