If your work comes from more than one source it is possible to be employed in one or more jobs - with your employer deducting tax and National Insurance - and self-employed in others.
If you're not sure whether your work counts as self-employment, ask yourself these questions:
If you answer 'yes' to most of these questions then you are probably self-employed already. To find out how to tell HM Revenue & Customs (HMRC) about your self employment, see the page in this guide on registering for tax and National Insurance.
The latest you can register with HMRC is 5 October after the tax year for which you need to submit a Self Assessment tax return - for example 5 October 2011 for the 2010-11 tax year. If you register late, you may be charged a penalty.
To better understand your employment status, use the employment status indicator on the HMRC website.
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