The CBI is to make the economic case to remain in the EU having reaffirmed a strong member mandate in an independent survey by polling company ComRes.
The majority of CBI member companies, which together employ nearly 7 million people (about one third of private sector employees) believe that it would be in the best interests of their business and the wider UK economy to remain inside the EU.
The survey revealed 80% of CBI members believe that the UK remaining a member of the EU would be best for their business. Overall, 5% say it is in their firms' best interests for the UK to leave the EU, with 15% unsure.
Carolyn Fairbairn, CBI Director-General, said: "The message from our members is resounding, most want the UK to stay in the EU because it is better for their business, jobs and prosperity.
"Walking away makes little economic sense and risks throwing away the many benefits we gain from being part of the EU.
"Our members tell us that having guaranteed access to a tariff-free market of 500 million people, and to more than 30 global trade deals covering 50 countries, are significant advantages that outweigh the frustrations.
"A minority of members want to leave the EU. We will continue to respect and reflect their views and campaign for EU reform to get a better deal for all businesses.
"However, most CBI members are unconvinced that alternatives to full membership would offer the same opportunities. We have yet to see those who seek to leave the EU present a compelling vision of what this would mean for jobs and growth.
"We will not align ourselves with any campaign. Though prosperity, jobs and future living standards matter to many people, we recognise there will be other considerations. It is not our place to tell people how to vote, but the CBI will play its role in making the economic case for remaining in the EU."