This page looks at what to do if you have paid too much tax on your employment or pension income.

A key part of Self Assessment is calculating your tax (and, if appropriate, self-employed National Insurance contributions and student loan repayments) due for the tax year. In most cases, HMRC perform this calculation for you based on the information you include on your tax return. 

If you were required to submit a Self Assessment tax return for a particular tax year to HMRC but you did not do so, HMRC may eventually send you a letter which sets out a ‘determination’ of the tax they think you owe for that tax year. If you failed to file more than one tax return you may get ...

Self Assessment payments usually become due on 31 January each year. Sometimes payments are also due on 31 July too. Here we explain which Self Assessment tax payments are due on each of these days. 

To avoid being charged a late filing penalty, make sure you understand when your Self Assessment tax return should be filed.

You must keep records to support the information you report to HMRC on your Self Assessment tax return or through Making Tax Digital for income tax. Here we look at what you need to keep, and for how long.