National Car Rental has called for fleets to rethink their approach to transport following the survey.
John Leigh, senior vice president of National, said: 'Now more than ever before, daily rental and car sharing schemes should be considered as cost-effective alternatives to company cars.
'Car sharing should also be considered as an ideal alternative for smaller companies that operate a smaller fleet of company vehicles.
'With the threat of taxes on workplace parking and congestion charging, the car club should be especially valuable.
'The service enables companies to pick their vehicle requirements on an almost day-to-day basis, making the company vehicle a more worthwhile tool and allowing firms to apply a 'green' policy to transportation without having to cut any corners on performance or productivity.'