If you’re a Mighty client, there’s a good chance you’ll need to register for Self Assessment and file a personal tax return. Therefore, this guide covers:
As a director of a limited company, you'll likely receive income that is not fully taxed through payroll: dividends. These dividends need to be reported within your Self-Assessment so that the associated tax can be paid, so it is compulsory that you register for Self-Assessment and file a Self-Assessment tax return (sometimes called a personal tax return). However, there may be other reasons that you need to register, even if you haven't received dividends, such as:
In any of these situations, you are required to register for Self Assessment and submit a tax return for the relevant tax year.
HMRC have a video (shown below) talking through how to register for a Self-Assessment tax return:
Here are the key steps:
When should you register?
If you need to file a tax return for the first time, HMRC normally expects you to register for Self Assessment by 5 October following the end of the tax year. If you miss this deadline, don’t panic as it's more of an informal one, but you should still register as soon as possible.
It’s common for new directors (especially in their first year) to register later in the year. If you register late and don’t receive your UTR in time to file your tax return by 31 January, HMRC will usually not charge a late-filing penalty, as long as you registered promptly once you realised you needed to file and submit the return as soon as you’re able.
Once registered, HMRC will expect a personal tax return for any tax year in which you needed to file. The tax year runs from 6th April to the 5th April the following year. So, for example the 2025/26 tax year runs from 6th April 2025 to 5th April 2026. The deadline for filing/paying any personal tax is the following 31st January, so for the 2025/26 tax year, this would be 31st January 2027.
Some clients choose to file their personal return themselves. Because of that, we do not include personal tax returns in our core subscription. However, if you’d like Mighty to handle it, we charge £125 + VAT to prepare and file your personal tax return. We’ll ask you to complete a short questionnaire, then we’ll prepare a draft return for your approval before submitting it to HMRC.
If you need help, drop us an email at support@mightyaccounting.com.