The survey, which was carried out by marketing agency , found that more than two-thirds of the companies surveyed expect an economic downturn this year.
Asked what the most effective marketing methods would be in a downturn, companies most commonly cited direct mail, search engine optimisation and updating their website.
Online activities, including social networking and blogs, are undervalued by small and medium-sized businesses, with only 11% of the companies surveyed considering them as a form of B2B marketing.
The survey also found that only half of the businesses had updated their website in the last month, despite research indicating that an up-to-date website was the most cost-effective way of marketing a business.
Ben Harris, managing director of New Brand Vision Group, said: "Many SMEs will not have been in business during the last recession and won't anticipate how they could be affected. It's worrying that with so many firms expecting a downturn, so few are actually taking steps to plan for it.
"This 'wait and see' approach may weaken their position if and when a downturn does take hold. Businesses should be armed and ready with their marketing and other business materials prepared, so if the hard times do hit they can immediately become proactive in generating new business."
Separately, the survey asked participants to name their most influential brand for 2008, with US presidential candidate Barack Obama and The Conservative Party among the most popular answers. Others included the Beijing Olympics, London 2012, Virgin Money and Apple.