R&C Brief 50/09 outlines the application of tax, national insurance and national minimum wage legislation on temporary workers. The brief is relevant for businesses involved directly or indirectly in the provision of temporary workers to end clients, end user businesses provided with temporary workers and temporary workers.
The Brief deals with arrangements described as 'Travel and Subsistence Schemes' or 'Mobile Worker Schemes'. These schemes are said to be operated by businesses involved in the supply of temporary workers to end users: Employment Businesses and umbrella companies. HMRC describes these labour supplying businesses as seeking to obtain a tax and National Insurance advantage by the creation of overarching employment contracts to enable temporary workers who would not otherwise be entitled to tax relief on travel and subsistence expenses to gain such tax relief.
Full details of HMRC's compliance activities in respect of these schemes is available here