Sean Donahue

Email Subject Lines: Words, Order as Critical as Length

January 26th, 2009

The standard email marketing rule is that shorter subject lines are usually better than longer ones. But like all rules, this one has its caveats and exceptions.

A new white paper from marketing services firm Epsilon analyzed subject lines from more than 568 million client emails to determine the influence of length, word order and content on open rates and clicks. The major takeaway:


– While it is important to keep subject lines as short as possible to convey your message, the choice of words and the order in which you place them is just as important to boosting response rates.

In fact, one of Epsilon’s conclusions – that marketers should front-load subject lines with the most important information – is precisely what we discovered in an analysis of our own email newsletter subject lines conducted last year. Here are a few of the trends we uncovered among our best-performing subject lines.

– Convey the benefit readers will receive from the email within the first two words of the subject line, such as:
o “Top 12 Email Newsletter Mistakes”
o “Best Time to Send Email: Test Results
o “How to Conduct Email Audits”

– Use the right “trigger words” early in the subject line. Trigger words can be numbers or hot-button industry terms, such as:
o “CAN-SPAM – Must-Know Updates”

– Hot brand names in subject lines can improve open rates. For example, some of our top performing subject lines included:
o Google AdWords: 8 Tips to Lift ROI
o Use Facebook to Market Yourself & Your Company

So, while keeping your subject lines short is important, focusing solely on length without paying attention to word choice and word placement won’t deliver optimum results. And don’t forget to conduct your own tests with your own audience to find the right approach.

Epsilon white paper: Rethinking the Relationship between Subject Line Length and Email Performance: A New Perspective on Subject Line Design http://www.epsilon.com/Epsilon_SubjectLine_WhitePaper.pdf

Previous MarketingSherpa article: 4 Takeaways from MarketingSherpa’s Newsletter Subject-Line Analysis

H/T to Tamara Gielen, who blogged about this white paper:
http://www.b2bemailmarketing.com/2009/01/subject-line-research-reveals-content-is-as-important-as-length.html

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  1. January 27th, 2009 at 11:34 | #1

    Your links don’t work as advertised 😉 Nonetheless, thanks for subject line examples and additional links.

  2. Andrea Ziadi
    January 31st, 2009 at 11:47 | #2

    Is it legal to email a contact list that has double-opted in to one newsletter, and inform them of a new newsletter that we are creating, providing them with a link to sign up for the new newsletter if they so wish?

  3. February 2nd, 2009 at 18:10 | #3

    Great tips that every marketers needs to know. Thanks for the info, Sean!

  4. November 11th, 2011 at 06:40 | #4

    Well written…It’s so true subject matter is as important in email as it was in traditional paper letter.

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