There's significant evidence that consumers are more likely to open emails whose subject lines contain the brand name of the sender. For instance, nearly half (48.8%) of consumers are attracted to emails that have the brand name of the sender in the subject line, according to Return Path's Third Annual Holiday Email Consumer Survey. That makes it almost as powerful as subject lines that offer a discount or free shipping, which 49.6% of respondents said made a subject line catch their attention.

A recent study from Silverpop, Email Creative That Works, found that B2C companies with branding in the subject line enjoyed open rates of 32% on average compared to just 18% for emails without. And in a recent Internet Retailer article, Barry Stamos, the senior director of strategy for Responsys, said that featuring the company's name in the subject line "can increase open rates by 5% or more."

Given the apparent benefits of this subject line tactic, I examined several months' worth of emails for 99 of the major retailers that I track via RetailEmail.Blogspot to see how frequently they used their brand names in their subject lines. I divided them into three buckets: those that used this tactic always or usually (that is, in at least 80% of their emails), sometimes (between 20% and 80%), and rarely or never (less than 20%). What I found was that only 13% of retailers did it always or usually, 20% did it sometimes, and 67% used their brand names in their subject lines rarely or never.

However, there are some grey areas that potentially boost these numbers a little. For instance, while AbeBooks doesn't include its branding in the subject line, it does include the name of its newsletter, The Avid Reader, in every subject line (i.e.," 2/14 - The Avid Reader: The Most Valuable Books Sold in Sci-Fi & Fantasy"). And Barnes & Noble does something similar, always starting its This Week at Barnes & Noble newsletter with "This Week" (i.e., "3/6 - This Week -- Coupons, Jodi Picoult, Kurt Andersen, More").

And then there's Bluefly, Buy.com, Neiman Marcus and TigerDirect, among others, which regularly use manufacturers' brand names in their subject lines, as in these recent emails:
Bluefly, 2/22 -- "Fresh Coat: New Arrivals for Spring Featuring Michael Kors, Marc Jacobs, Via Spiga"
Buy.com, 3/8 -- "ViewSonic 20" Widescreen LCD, SanDisk 4GB Flash Drive, WD 500GB Hard Drive"
Neiman Marcus, 3/7 -- "JIMMY CHOO: New spring handbags, now online + FREE SHIPPING"
TigerDirect, 2/2 - "Acer 3.2ghz PC $399...17" Samsung LCD $129...56" HDTV $1099"

I haven't seen any research on this, but it's likely that consumers respond to manufacturers' brands in subject lines just as strongly as they do the sender's brand -- and in some cases, more so.

As with all things email, you should test this tactic to see if your particular audience responds to it. It appears that in at least one case, that of Kmart, the tactic didn't deliver. Prior to Aug. 29, the retailer began all of its subject lines with "Kmart:" but since then has used its brand name in its subject lines only once. Presumably, Kmart hasn't seen open rates dip since dropping its name from its subject lines.

This commentary is insightful. I recommend it to others.