Tax for the self-employed Self-employed income tax
If you're self-employed, you are responsible for declaring and paying income tax on the profits from your business.
This guide talks you through the basics of what you need to do to calculate how much income tax you pay.
Self-employed income tax
Self-employed people pay income tax on their profits, rather than their gross income. To work out the correct figure, you need to deduct business expenses from your business income.
You can also claim capital allowances and deduct any losses carried over from previous years. The resulting amount is your taxable income.
Find out more: Self employed capital allowances - find out what you can claim as tax-deductible
Self-employed tax return
To work out whether you must pay income tax, you need to fill in the self-employment supplement (SA103) as well as the main tax return.
Usually this is sent to you automatically once you've registered as self-employed.
If you have registered but don’t receive one, you can download it from the HMRC website or get a copy by calling the HMRC orderline (0845 900 0404).
Tax return supplements
There are now two tax return supplements – a short one and a full one.
You can fill in the short one if your turnover for 2015/16 was £77,000 or less and no complications, such as a change of accounting date, apply.
However, you cannot use the short one if your accounting period is not the same as your basis period (i.e. your business year), so you may not be able to use it in the first year. It's up to you to make sure you get the right supplement.
Partnerships and limited companies
The supplement and the advice in this section apply to people who are sole traders. If you are in partnership, you need the partnership supplement.
If you run your own limited company, you are an employee of the business and need the employment supplement.
- Which? tax calculator- check your 2015-16 tax bill with our tax calculator
- Tax returns explained - find out what you need to do to complete one
- Call the Which? Money Helpline - if you have a question about tax
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