The topic of email subject lines always generates interest (and some debate) as marketers try to fight through inbox clutter that sees consumers receiving a reported average of 416 commercial emails per month (and that was 2 years ago). A couple of recently-released studies provide some fresh data to review.
First, a look at a study from Return Path [PDF], based on an analysis of “9 million subject lines received by more than 2 million subscribers from January 1st through February 28th, 2015 using its Subject Line Optimizer solution.”
Right off the top, an interesting finding: the analysis finds no correlation between subject line length and read rate. That stands in apparent contrast to research from MailerMailer last year, which had linked shorter subject lines to higher open and click rates (though significance was not tested). Read the rest at MarketingCharts.