Being both self-employed and employed
If you're both self-employed and employed, then both need to be reported on your tax return.
Here's how it works.
If you are self-employed and earning over £1,000 from your self-employment activity, then you need to register with HMRC and file tax returns.
When you fill in your tax return, you also need to include information about any employment you have had. This will come from the P60 or P45 forms that you will have received from your employer (income such as Jobseeker's Allowance and Pension are reported in a similar way); in untied you can also bring this information from your HMRC account.
Generally there won't be any more tax to pay on your employment. The reason you need to include it though is because this would often take up your personal allowance - meaning it won't be available as well for your self-employment.
The table below reflects this using 2021/22 numbers as an example (this is based on a salary that exactly matches the personal allowance):
| Annual self-employed earnings
(income – expenses)
| Tax if you’re only self-employed
(income tax + national insurance)
| Tax on your self-employment
if you’re also employed (may be higher)