Started Self-Employment Halfway Through the Year: Which Self Assessment Return to Use?
If you began working as a sole trader partway through the UK tax year, you still need to complete a Self Assessment tax return covering the entire tax year from 6 April to 5 April the following year. HM Revenue and Customs (HMRC) requires you to report all income received during that tax year, including income from before you started self-employment.
Which Tax Return Covers Your Income?
The standard Self Assessment tax return form (SA100) is used regardless of when you started trading during the tax year. You will include details of your self-employment income and expenses on the relevant self-employment section (SA103S for simpler accounts or SA103F for more detailed accounts, depending on your business size and circumstances).
For example, if you started your business on 1 November 2023, your tax return for the 2023 to 2024 tax year (6 April 2023 to 5 April 2024) must include:
- Any income you earned from other sources before 1 November 2023, such as employment income or savings interest
- All income and allowable expenses from your self-employment starting 1 November 2023
You do not file a separate return for the months before you started self-employment; all income and gains for the tax year are reported together in the single return for that year.
Registering and Deadlines
If you have not already registered for Self Assessment, you must do so by 5 October following the end of the tax year in which you started trading. For example, if you started self-employment in November 2023, you need to register by 5 October 2024.
Failing to register on time may result in penalties. After registering, you will receive a Unique Taxpayer Reference (UTR) and can file your tax return online or on paper.
Record-Keeping
Keep accurate records from the date you started self-employment, including invoices, receipts, and bank statements. This will help you complete the self-employment section of your return correctly. You should also keep records relating to any other income sources for the tax year.
Summary
- Use the standard Self Assessment tax return (SA100) for the full tax year, regardless of when you started self-employment.
- Include all income for the tax year, not just your self-employment income.
- Register for Self Assessment by 5 October after the tax year you started trading.
- Maintain good records from the start of your self-employment and for any other income sources.
For detailed guidance or to register, check the official HMRC Self Assessment information.
Official reference: https://www.gov.uk/self-assessment-tax-returns. Always check the latest official guidance. Related forms: Browse our form category.
Important: This article provides general information. Government rules, forms and procedures can change, and this article may not reflect the latest updates. Check current GOV.UK guidance or the relevant authority before relying on it. ITG & Co. is independent and is not affiliated with a government department.