This depends on the contractual relationship you have with your employer. Every year court cases hang on this distinction, and unfortunately there is no clear definition. However, there is a rough rule of thumb:
Many people are happy to be self-employed, and some occupations such as journalism are likely to have a high proportion of self-employed workers. However some unscrupulous employers deliberately try to prevent the people who work for them from becoming 'employees', so that they do not enjoy many important employment rights.
There are a lot of grey areas here, so if you are unsure, you would be best advised to seek individual advice. Contact your union if you are a member, or use one of the resources on our free help page
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