Q. I have prepared my 2022 tax return for submission but looking at previous returns I found that I’d made an error when completing my 2018/19 tax return, resulting in an overpayment of tax. Am I able to get my money back?
A: The self-assessment rules limit the time you have to claim tax relief. As an individual or company, the time limit for submitting an amended return is usually one year from the deadline for submitting the return you want to change. So, to amend the 2020/2021 return, for example, you have until 31 January 2023. It is too late for the 2018/19 return to be amended but a claim can be made for 'overpayment relief'. Further information on this can be found in the government’s Self Assessment Claims Manual.
Except where legislation specifies to the contrary, the general rule is that relief must be claimed within four years from the end of the tax year to which the claim relates for personal taxes, and four years from the end of the accounting period for corporation tax. Therefore, so long as this claim for the year 2018/19 reaches HMRC by 5 April 2023 you can claim. Please note that this claim must be in writing.