4 subject line tricks to boost e-mail open rates

Subject lines are to e-mail as teaser copy is to direct mail.

The subject line is the first thing people see when they receive your e-mail message. If it grabs their attention and creates curiosity, your message gets opened and read. Otherwise, your message gets deleted.

Everyone has their own ideas about what makes for good subject lines, but MarketingSherpa recently crunched the numbers on a year’s worth of newsletter data. The results produced four key strategies.

1. “Show value in the first two words”

You can’t be clever or mysterious. People get way too much e-mail to waste time on anything that doesn’t convey an immediate benefit. Take a look at the subject lines from Sherpa’s top 10 newsletter performers:

Top 12 Email Newsletter Mistakes
Simple Email Link Change Lifts Clicks
CAN-SPAM – Must-Know Updates
Best Time to Send Email: Test Results
6 Actions to Lift Clickthroughs: New Data
Your Copy of Annual Email Study Results Enclosed
HTML vs Text: Which Works Better?
Newsletter Design Exclusive Data
Email Audit PDF: How-to & Checklist
How to Conduct Email Surveys

I’m not sure where they get the idea that it’s specifically the first two words that make a difference, but it’s clear that all of the subject lines convey a benefit quickly and clearly, with relevant words near the beginning.

Contrast these to Sherpa’s bottom performers:

Target Referrals & Abandons
Eastern Europe Factbook
Tailor Lists to Reach Exec Moms
Call for Speakers – Email Summit & Expo ’09
Your Input, Please: Annual Marketing Questionnaire
How Wholesaler Lifted Orders 13%
Buyer’s Guide to Top Survey Vendors
Turn Customer Queries Into Profit
Test Your Email Practices; Friday Award Deadline
Alert: Analysis of New CAN-SPAM Rules

Some of these subject lines signal interesting content, but they don’t telegraph the same immediate value as the top performing subject lines.

2. “Find the right trigger words”

In addition to quickly conveying actionable information, Sherpa concluded that there are certain “triggers” that can increase the open rate. A trigger can be “a name, the use of numbers, the number of characters in the subject line, the use of an industry phrase, or the appearance of an unusual word.”

One of these, short subject lines, is shown clearly in Sherpa’s top four performers, which were around 30 to 40 characters long. That squares with the rule of thumb that subject lines should be about 35 characters.

However, don’t get too wound up about length. Content is always more important than structure, so long subject lines can work if they’re used at the right time, such as with a white paper or other freebie.

I would suggest the same advice for subject lines as ad headlines: take your time, write dozens, and play with the wording before you decide which way to go.

3. “Watch the hard sell”

Hard sell can work with certain consumer segments, but many people are turned off by overblown language and unbelievable promises. Business buyers can be especially sensitive to hard sell. Here are 10 of Sherpa’s worst performing B2B subject line:

Please Take Quick Tech Survey Today
Call for Speakers: Demand Gen Summit
You’re Invited – Biz Tech Webinar June 17
Early Bird Special for Demand Gen Summit
Nominations to Speak at Email Summit
Podcast: Contests for Lead Gen
Podcast: Get Wicked Good Leads
Game Lifts Sales – Test & Results
How to Weed Out Consumer Leads From B-to-B Campaign
Touched by Angels

These are hardly examples of over-the-top copywriting. But they do have a somewhat self-serving tone and don’t offer obvious personal value. I think most important here is that it’s just not clear what you’re getting with these subject lines.

4. “Hot brands work across sectors”

This one could fall under #2, “Find the right trigger words.” Recognizable brand names, particularly brand names that are interesting or relevant to the recipient, draw the eye and carry loads of meaning. Here are three more effective Sherpa subject lines:

Google AdWords: 8 Tips to Lift ROI
Get Listed on Wikipedia – 3 Ways + Monitoring Tips
Use Facebook to Market Yourself & Your Company

MarketingSherpa’s analyst is quick to point out that these subject lines may have done even better if they had used “Wikipedia” and “Facebook,” two highly recognizable brands, in the first two words. On the other hand, following any rule slavishly can lead to awkward copy, so you have to balance rules of thumb with clarity and common sense.

For more info on e-mail marketing, check out MarketingSherpa’s 2009 Email Marketing Benchmark Guide.

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One Response to “4 subject line tricks to boost e-mail open rates”

  1. Cynthia Maniglia on December 5th, 2008 6:43 pm

    And I thought Sherpa was just the maker of my dog’s carrier bag…

    Seriously, though – great post. Thanks for sharing!

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