As noted in our last post on 2013 trends, using social login can help merchants individualize the shopping experience for brand followers. And research shows that consumers appreciate the option: according to marketing firm Monetate, on the eCommerce site.

But despite the potential upside, few of the largest U.S. merchants have taken the opportunity to implement social login — just 30 of the merchants in Internet Retailer’s Top 500 have done so, according to marketing firm Sociable Labs. The threat of brand dilution posed by displaying other sites’ logos on the eCommerce site, and the fact that merchants don’t own the data shared by social login users, are perhaps among the reasons driving this reluctance. As , the key is to avoid assuming social logins can solve all a site’s conversion and engagement challenges. Merchants need to assess the potential upside of social logins for their own unique brands and act accordingly.

Despite the caveats, we believe social logins have the potential to drive significant brand engagement, and worth pursuing. But doing so is more than a matter of simply putting a button on the first page of checkout. To maximize the effectiveness of social login, merchants should consider the following strategies:

Know which logins matter to your audience. By far the most popular social login is Facebook’s, according to the Monetate study; fully 60% of shoppers use it, while other social networks’ logins each have less than 15% share. Given that , according to the Pew Internet & American Life Project, most merchants considering social login should plan to implement . But depending on their audience, merchants should also consider adding logins from other social networks, from Twitter to LinkedIn. Careful study of analytics and an assessment of which social networks have the largest audience of brand followers can help merchants assess which logins to use. The key is to offer the right mix for the audience without presenting an overwhelming array of options for shoppers.

Integrate fully. Too many merchants who use social login go on to ask shoppers to set up a separate account password for the eCommerce site — but the aim of using social login should be to smooth the path to purchase, not erect more barriers. Of course merchants should strive to establish their own direct relationship with shoppers; but they should implement a phased approach that encourages existing social login users to deepen their relationship, rather than forcing the issue up front. 1-800-Flowers gives Facebook Login users full access to the eCommerce site’s account tools, such as reminder services and address book creation, without creating an additional password.

Develop true social shopping opportunities. As a corollary to the above, merchants should make it worthwhile for shoppers to connect via social login by doing more than pre-populating a few checkout fields. Easily-shareable wish lists are a good starting point, but merchants should also develop shopping experiences that draw on shoppers’ social profiles to bring their network of friends and their personal preferences into play. Apparel merchant Charlotte Russe enables social login users to view a real-time stream of what items are being liked and commented on. Shoppers can filter the stream to view only their friends’ picks, and control whether their own selections are shared or not.

Merchants should also consider reminder services that incorporate social login users’ friend feeds. Amazon.com not only lets shoppers know which Facebook friends have birthdays coming up soon, but also makes gift recommendations based on friends’ prior purchases and history of product “likes” on Facebook.

Give users privacy controls — and message prominently. With Facebook and other social networks often grabbing headlines for privacy gaffes, it’s crucial for merchants to clearly outline how social login functionality will work, what user data will be culled from their social profiles, and what information will be shared with users’ friends by the merchant — and social login users should be able to exercise privacy control at multiple points along the engagement path. When designing their social login experiences, merchants should pay special attention to:

• Signup messaging. Shoppers offered the option of a social login should understand the benefits and what information will be shared before beginning the process. Then, once they’ve opted to use the social login, they should be able to exercise control over how their information will be shared. On the first page of checkout, Wine.com gives shoppers an extensive explanation in a pop-up window of how Facebook Login works. Those who opt to use the social login are then notified of which data the tool will use and given the option to control how information is shared on the social network.

• Sharing “likes.” When social login users add products to their list of favorites or “like” the items, they should be alerted to how that information will be shared — and given the option to edit the settings. Department store Barney’s launches a pop-up window when a shopper first uses the “Favorites” tool and lets shoppers select whether or not to share their picks.

• Global control. From any page of the site, shoppers should be able to access their account and turn social sharing on or off; they should also be able to log out completely. Accessory retailer Claire’s offers a drop-down menu in the global navigation that enables shoppers to switch sharing on or off without leaving the browsing experience; users can also opt to log out completely. A fly-out help menu clearly delineates how sharing works and offers the further option of disconnecting from Facebook altogether.

Are you using or considering social logins for your site? Why or why not?