Simple Tax Calculation

[pawncob]

A client has enquired as to the finality of the STC.
His return was submitted in April 2024, and the on line calculator showed tax due of c £5500.
He's now received a STC showing £4500 as due for 23/24. The STC doesn't include Dividend income.

The question arises, if he pays based on the STC, will HMRC ever realise their mistake?
Does anyone at HMRC (or their software) compare the real calculation with the STC?
Opinions invited.

[D&C]

I think you are overlooking a vital point here.

Current situation appears to be tax return submitted showing c£5,500 tax due.

And a Simple Assessment (I'm assuming that's what you mean by Simple Tax Calculation) has been issued for the same tax year for £4,500.

So at the moment there is a total of c£10,000 tax being charged.

Given a tax return will always trump a Simple Assessment how does paying the £4,500 help your client?

Isn't the better course of action to notify HMRC that the Simple Assessment needs to be cancelled as a return has been filed for that tax year?

[Botcamper]

I would agree with D&C

I submitted a self assessment tax return as required for 2023/24 and paid the tax due. Six months later HMRC issued me with a simple assessment asking for the same amount of tax again. The two systems do not recognise each other so you need to get the simple assessment cancelled.

[Green shed man]

Is this a growing problem, I wonder. It has been suggested to me that these Simple Assessments, issued after filing tax return and paying tax due, may not merely be errors by HMRC employees, but perhaps something worse. I have now seen another case, where the 2023/24 tax return was filed in October 2024 and tax correctly paid in January 2025. But recently (April 2025) a Simple Assessment has been received. The Simple Assessment shows the correct amount of State Pension but does not mention the person's dividend income at all. And as regards interest, the amount in the Simple Assessment is incorrect. This is still a double assessment. I have seen other similar cases before this and have written or helped to write several letters to HMRC since January. One of those cases has been resolved with an apology from HMRC. It is so depressing to see again and again that the Personal Tax and Self-Assessment / Business Tax parts of the account show completely different information. Also this causes very considerable stress and worry for the people affected.

[pawncob]

Thanks for the replies.
He's decided to ignore it.
There's no point in writing to HMRC, as they won't deal with before the July payment becomes due.
The amount on his tax account is correct, which is all that matters.