you will pay Class 1 National Insurance contributions and be eligible for certain Social Security benefits in the UK in the same way as a mariner who is resident or domiciled in the UK.
If you have a valid form A1 or E101 from another Member State exempting you from UK contributions, then you do not pay in the UK.
From 1 May 2010 mariners are to be insured in the State where their vessel is flagged under European Community Regulations 883/2004 which operate in the EU.
Unless:
Where the mariner is remunerated by an undertaking in the Member State where he resides, the legislation of the Member State of residence applies. Under these rules, the person paying the remuneration is to be treated as the employer under the legislation that applies.
Steve is resident in the UK. He works on a Dutch flagged vessel. Steve is paid his remuneration by an agent of the shipping company. The agent is in the UK. Steve is subject to UK Class 1 National Insurance and the agent is treated as his employer for National Insurance purposes.
A person who comes within the exception must obtain form A1 or E101 from the country of residence.
Before 1 May 2010 the basic rule was that mariners were insured in the 'flag state' under European Community Regulations 1408/71. However, the exceptions to this basic 'flag state' rule were slightly different:
If the application of the new rules from 1 May 2010 would change which Member
State's legislation applies, you should contact HM Revenue & Customs for
advice.