SA29. Your social security insurance, benefits and healthcare rights in the European Economic Area
Insurance and contributions
10. Self-employed in the UK
If you are normally self-employed in another EEA country and you come to do self-employed work in the UK, as long as you do not expect to be working in the UK for more than 12 months, you will stay insured with the other EEA country. You will not have to pay UK contributions.
You must have form E101, to tell us that you are still insured under the other EEA country's scheme. You must apply for and obtain form E101 from the insurance authorities of the country you usually work in.
If you do not have form E101, you will be asked to pay UK NI contributions.
It may happen that your work lasts longer than 12 months, although you did not expect it to. You can carry on being insured under the other EEA country's scheme for not more than another 12 months. But HM Revenue and Customs must agree to this extra time. Before the end of the first 12 months you should ask for form E102. You can get it from the insurance authorities of the country where your contributions are being paid. Use form E102 to ask if you can carry on being insured in the other EEA country. Send the form to HM Revenue and Customs.
Your work may still not be finished when the second 12 months are over. Or you may not be allowed to stay insured under the scheme of the other EEA country after the end of the first 12 months. If so, you must start paying contributions to the UK scheme.
If you are not included in the rules in this section and you work in the UK, you will usually have to pay UK contributions as soon as you start work. To do so, you must have a UK NI number.
If you do not have a UK NI number, you must apply for one in person as soon as possible at a Jobcentre Plus or social security office. You can obtain the address of your nearest office from the telephone directory. They can tell you more about paying contributions in the UK.