From 1 June 2012, EC regulations 883/2004 and 987/2009 apply to European Economic Area countries: Norway, Iceland and Liechtenstein.
An important difference between the old and the new rules is that if a taxpayer works in the UK for a Norwegian, Icelandic or Liechtenstein employer and is paying National Insurance contributions in the UK, the employer may also have to start paying UK contributions.
The new rules also apply to self-employed people moving between the UK and Norway, Iceland or Liechtenstein.
Under special transitional rules, taxpayers who were subject to the legislation of the UK or Norway/Iceland/Liechtenstein under the old rules may be able to carry on paying to the first country until there is a change in their circumstances.