E-Mail Open Rates Hinge on 'Subject' Line - eMarketer
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E-Mail Open Rates Hinge on 'Subject' Line

Turning off Caps Lock doesn't hurt either.

October 31, 2007

Personalized e-mails boost open rates, according to a MailerMailer study. The e-mail service provider found that personalized "subject" lines in particular increased the number of times recipients opened their mailings.

The "subject" line is so important that, even when marketers have recipients' permission, the wrong line can still mean trouble. "The e-mail’s 'from' and 'subject' lines become key elements that help recipients quickly decide whether the e-mail is spam," said David Hallerman, senior analyst at eMarketer.

E-Mail Marketing Open and Click Rates* Worldwide, by Level of Personalization, 2007

"Yet legitimate marketers confuse such seemingly simple issues by sending messages from different groups within their companies," Mr. Hallerman said, "and hence with various 'from' lines.

"Or they use 'subject' lines that they hope will entice the recipient but are often not clear enough," he said.

A December 2006 study by the E-Mail Sender and Provider Coalition and Ipsos confirmed how crucial "from" and "subject" lines are. About seven in 10 US Internet users said they judged these lines when deciding whether to report an e-mail as spam.

Select Criteria Used by US Internet Users to Decide Whether to Click on an E-Mail

The MailerMailer study also found that open rates have continued to decline, as they have since 2004, as more people started using e-mail programs that disable the “automatic image downloading" setting.

To track open rates, HTML e-mails contain an invisible image measuring 1x1 pixel. When a recipient enables images to display, the sending servers can track when the image was displayed and by whom.

E-Mail Marketing Unique Open Rates Worldwide, 2006 & 2007

Even though open rates have gone down, click rates remain steady, suggesting that people are still reading their e-mail despite the lower-reported open rates.

Learn what else can go wrong before you hit "send." Read eMarketer's E-Mail Marketing: Getting Through to Customers report.


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