Disappointing response when I asked about my tax re-calculation

I completed my self assessment tax form & submitted it on 15/1/2424. On 22/1/24 I contacted the HMRC Chat function as I noted that the payable amount had been increased from the calculated amount on my submitted tax form. When I viewed my submitted tax form on the system it still showed the lower amount which I had calculated. There was no explanation or evident re-calculation regarding why I was being asked to pay more. On the Chat function I was told that I would wait for over 30 minutes. 15 minutes later I was disconnected from my HMRC account as 'I had not done anything on it for 15 minutes', and I was also disconnected from the Chat function. The following day (23/1/24) I contacted the Chat again and after 30 minutes I was connected to an advisor who stated that I was expected to pay the larger amount. They said they could not explain why I was seeing a lesser amount on my tax form calculation, and perhaps that was due to an error on the system. When I asked why I was being asked to pay more, I was repeatedly told the 'new' amount again, and advised that if I over-paid any tax I would be reimbursed. When I was typing a message asking a further question (it was about 4.55 p.m.) the advisor 'ended the Chat', giving the reason that 'I had not inputted any further messages'. The following day (24/1/24) I contacted the Chat again, asking the same questions. The advisor advised me that my "state pension had been repaired" and gave me the relevant (higher) figure. When I asked if I could see evidence/the re-calculation, they said they could send it to me. I asked if they would email it to me, and they said they could only send it to me by post. I pointed out that there were only a few days left until 31/1/24 and it was possible I could incur a fine for late payment of tax, if I did not receive the letter by then. Again while I was typing another message, I saw that the advisor had 'ended the Chat' without warning. I have paid the requested amount, but I am very concerned about the poor service I have had and the apparent futility of contacting the Chat function for help. Is there no other way I could have had this sorted out? I was left feeling quite helpless and upset. If an advisor 'ends the Chat' there is nothing the person at the other end can do, apart from starting the process all over again. An advisor ending the Chat without warning is the equivalent of having the phone put down on you by a Help function, which is completely unacceptable. I'm posting this, not to argue with HMRC about the above (I think I just want to forget about it all now!), but I thought it might help if I share my experience with others - I would be very surprised if I have been the only one to have had this experience. I will also add a post to advise whether or not I receive the information/re-calculation I was promised by the advisor.

Hi, not hmrc admin but I might be able to provide an explanation for the difference in figures. There are a few common mistakes people make with their state pension. One is adding up all payments received in the tax year. This would be incorrect as state pension is taxable on the "accruals" basis. Which basically means how many days you were entitled to be paid for, irrespective of when it is actually paid to you. The other is taking their pension payment amount and multiplying it by 12. This is incorrect as it is paid every 4 weeks and 4x 12 = 48, not 52. I'm hoping that helps you check your return and gain some confidence that the amount you've paid is right, while you are waiting on the calculation.

Thanks for your very useful reply. I assume the first issue applied to me to me when calculating my state pension. Any idea how I can avoid this in future as I don't receive a summary about my state pension entitlement for each tax year.

On 29/1/24 I received a letter from HMRC dated 17/1/24, with the new, adjusted tax calculation. It was a relief to receive it but it would have been helpful to have known it would be arriving. I assume the Chat advisors I spoke to were unfortunately unaware that it had been sent, too?

Hi Dolly74 Cox,
I apologise that your chat was ended without a warning.
Regarding the state pension figure we would amend this based on the figure supplied by the department of works and pensions.
When you receive the amended calculation you can check the details.
The options to contact HMRC Self Assessment: general enquiries.
Thank you.