A quarter of e-retailers failed to respond to consumer questions posted on the retailers’ Facebook walls and also within the comments section of a merchant’s own posts, according to a new report from StellaService. The customer service vendor arrived at its finding by posing general questions to 20 retailers on the social network.

The findings come as consumers increasingly turn to social media to get answers from retailers about customer service issues. 27% of U.S. online consumers sought help through an online community last year, up from 7% in 2009, Forrester Research Inc. said in a recent survey. The StellaService report suggests that a number of retailers haven’t adjusted to that shift in consumer behavior.

Five retailers—J. Crew Group Inc., One Kings Lane, RadioShack Corp., Rue La La and Victoria’s Secret Direct—failed to respond within 48 hours  of a question being posted on the their walls, StellaService found. 13 retailers failed to respond within 48 hours of a question being posted within the comments section of their own posts.

Five retailers—Fab.com, Cooking.com, Crate and Barrel, Victoria’s Secret and Rue La La—deleted consumers’ questions without answering them. The report calls that a mistake, as several consumers might have the same question and a merchant’s response could resolve multiple shoppers’ issues in a single stroke.

Some retailers were quick to reply. B & H Foto & Electronics Corp. responded to questions within two minutes. The electronics retailer, along with Gap Inc., Bed, Bath & Beyond, JackThreads.com, and Williams-Sonoma Inc., were the only retailers that hit all the right marks in the report, responding to questions on their walls, as well as in comments, and not deleting those inquiries.

“For service and support-oriented companies to open themselves up and extend themselves to their Facebook brand page, they have to accept that their customers are there,” says Wendy Lea, CEO of Get Satisfaction Inc., which offers an application that helps retailers respond to customer service issues on Facebook. Those consumers are going to ask retailers questions, she says, and merchants can’t afford not to respond.

Lauren Freedman, president of consulting firm the E-tailing Group Inc. will speak during a session entitled “What shoppers want: Listening in on the consumer voice” at the 2012 Internet Retailer Conference & Exhibition in Chicago in June.