The firm – a leading UK fleet management and funding specialist – undertook a survey of 633 employees who had privately funded cars, with the results, when extrapolated across Britain, indicating that there 14 million cars in the “grey fleet”, with 9 million of these used for work purposes on a regular basis.

Such drivers pose a significant challenge for organisations in terms of employee safety, the environmental impact of their vehicles and in extreme circumstances the potential for corporate manslaughter charges.

Of those organisations surveyed who offer company cars, one in five businesses (20%) failed to always carry out adequate checks to see if their employees had the correct insurance in place to use a private car for work purposes. More than one in ten (12%) said they only undertook sporadic checks and a further 8% admitted they did not carry out any insurance checks at all.

Tim Porter, managing director of Lex Autolease, said: ‘It appears many organisations remain oblivious to the cost challenges, environmental impact and safety risks associated with employees using their own vehicles for work purposes. Our research suggests the grey fleet is significantly larger than the size of the UK’s company car fleet. This represents a significant risk management challenge that organisations of all sizes need to address.’