The Tax Return form can appear long and complicated because it has to be able to deal with a wide range of individual circumstances but only a very small number of the boxes on the return will need to be completed.
The basic return form SA100 has 8 pages and collects information about you, your investment and pension income if you have any, whether you wish to claim one of the principal tax reliefs and how you would like to deal with any tax payment or refund.
One page of the return asks about your main sources of income (employment, self-employment, income from property, overseas, trusts, capital gains and your residence status). There are supplementary pages for the return that deal with each of these. Unless you are completing the return on-line, you will have to ask HMRC to send you the supplementary pages or download them from the HMRC website here: https://www.gov.uk/self-assessment-tax-return-forms.
HMRC encourage everyone who can to file their returns on-line, but you can still file a paper return if you prefer. Note that the deadline for filing a paper return is 31st October following the end of the tax year (31st October 2024 for the 2023/24 tax year). The deadline for filing on-line is 31st January (31st January 2025 for the 2023/24 tax year). If you have filed a tax return on-line in the previous year, HMRC will not send you a paper return, but you can still file a paper return.
Notification to file a return.
Not everyone needs to file a tax return and HMRC only requires tax returns from people with particular types of income or more complicated tax affairs. HMRC will either send a letter with a blank tax return or, if you are registered for digital communication, you should be sent an email telling you to check your personal tax account for a notice to file letter.
If you have not been sent a notification to file a return you do not usually need to file one. This is unless you have income or gains that create a tax liability. In this case you are obligated to notify HMRC that you are subject to tax, and you will need to file a tax return for the appropriate tax year.
Normally, if you have not been sent a notification, you do not need to file a tax return unless you have income or gains that create a tax liability, in which case you are obliged to notify HMRC that you are subject to tax by October 5th following the end of the tax year.
If you are not sure whether you should file a tax return, see ‘do I need to file a tax return?‘
Short tax returns
There is a short (4 page) tax return that HMRC issue for some taxpayers with very straightforward tax affairs who must still file a tax return. This form (SA200) is not available from the HMRC website, and you cannot ask for a short return.
Tax return checklist
Here is a quick guide to filing your tax return:
- Gather all necessary documents: You will need documents for all of your sources of income. This can include a P60 FORM, as well as a P45 and/or P11D if you received one. You will need details of your investment income (and interest), property income, or any income from self-employment.
- Plan how you will submit your tax return: You can either do this online or on-paper (although remember the deadline for a paper tax return is earlier on 31st October, rather than 31st January).
- Complete the sections of the return that are relevant to you. The others you can leave blank. HMRC’s “How to fill in your tax return” is a useful guide updated every year. The 2024 guide is here: https://assets.publishing.service.gov.uk/media/6613fc00eb8a1b68a805e30f/SA150_Notes_2024.pdf.
- If you are not sure about any entry in the return, it is best to get advice. TaxAid can help if you are eligible, you can contact HMRC by phone or through the digital adviser, or you can ask a tax adviser. See the page on choosing an adviser at https://taxaid.org.uk/guides/taxpayers?highlight=chosing%20an%20adviser.
- Be accurate and honest, double check all the information you provide on your return. Mistakes or inaccuracies can lead to problems with HMRC and could result in penalties. It is best to be honest about your income and expenses to avoid any issues.
- If you file your return online, make sure you generate a submission receipt and print it out or save a copy.
Completing the return
Remember that you only need to complete the sections of the tax return that are relevant to your personal circumstances for the tax year covered by the return.
The following sections give some further information on what records you will need, what you need to put on your tax return and how the tax due is calculated and paid. They are NOT a comprehensive guide to filling in the return and you should seek advice if your circumstances are not straightforward as there can be penalties for mistakes or errors.
HMRC’s website also has videos and articles with useful information and online tools to help you complete your self-assessment. You can access this information here: https://www.gov.uk/guidance/help-online-for-self-assessment
