Why is my HMRC account showing different amounts due than GoSimpleTax?

Why is my HMRC account showing different amounts due than GoSimpleTax?

Unfortunately, the GoSimpleTax Support team are unable to provide an explanation for the difference in tax figures.

One of the reasons is that HMRC may have amended your return in the back-end. You'll receive HMRC's amended calculation in the post in due course if this is the case. It'll state the new calculation and there will be explanations of any changes made on the backend.

You'll have to call HMRC or wait for the letter from HMRC (in regards to the amended calculation) to understand the difference in tax due.

We advise that you pay your amounts due if you have this issue close to the deadline.

If you forward all pages of the letter you receive, we will be able to notify you of their changes - however, we will not be able to deal with HMRC on your behalf.