• by Erik Sass , Staff Writer @eriksass1, July 8, 2013

While Facebook may allow online influencers to reach large numbers of people, email is more efficient, as a larger proportion of the people reached via email actually become customers, according to a new study of social referral marketing campaigns by SocialTwist, titled “The Connected Consumer: Brand Advocacy Trends from 100+ Social Campaigns.”

SocialTwist looked at 119 social referral campaigns run over an 18-month period by leading brands and companies, including Sara Lee, Kimberly-Clark, Barnes & Noble, Unilever, Western Union, and MetLife. In each campaign, consumers were invited to share marketing messages, including special offers and coupons, with their circle of friends via a variety of channels, including social media and email.

Overall 3.2 million consumers participated in the social referral campaigns tracked by SocialTwist; of these, roughly 600,000 (19%) became influencers by choosing to share messages, and each influencer reached an average of 15 other consumers, for a total of nine million new consumers reached via social referral. However, only about 300,000 out of nine million (3%) actually converted to become new customers.

Different referral channels produced markedly different results, according to SocialTwist. For example, email was the favorite channel used by participants, with 55.4% of influencers sharing marketing messages via email, compared to 41.8% who used Facebook. On the other hand, Facebook was the most effective channel for reaching large numbers of people, accounting for 85.1% of all the new consumers reached, compared to 12.4% for email.

But email far excelled at conversion: among the 300,000 who converted to become new customers, 50.8% were reached via email, compared to 26.8% for Twitter and 22% for Facebook. Email fared especially well in certain categories, accounting for 62% of new customer referrals in financial services and 60% in retail.