Let's Get to the Subject

I love bringing up the subject of subject lines. Why? Because most people spend only a fraction of a second deciding whether to open, ignore, or delete a message. And the biggest factor impacting that decision is…you guessed it, the subject line. In fact, 33% of email recipients will open an email based on subject line alone and a staggering 69% of email recipients report email as spam based solely on the subject line, according to Convince & Convert.

While there is no magic subject line formula that will work for every business and email message, there are some proven tactics to optimize your subject lines and increase subscriber engagement…and some strategies to avoid.

Will the real Slim Shady please stand up?
To set your subject line up for success, it’s important to identify yourself before introducing the message. Be clear who the email is from by using a recognizable friendly from address. To differentiate the friendly from for different types of messages (i.e., customer service emails, loyalty program emails) test a variation at the end of your friendly from (e.g., [email protected]) so that subscribers may still immediately recognize your messages.

Also, be consistent. Using a consistent friendly from address eliminates the risk of subscriber confusion and spam complaints.

Oh no you didn’t 
Don’t bait and switch subscribers with misleading subject lines. Make sure the subject line accurately reflects the message content, to avoid your email being marked as spam. I encourage subject line creativity as long as you’re not pulling the rug out from under your trusting subscribers via misleading messaging.

Just do it
Give recipients a specific reason to open the email, whether it’s a compelling offer, exclusive news, helpful tips, or another benefit driven prompt. While this may seem like a given, when was the last time you considered why your subscribers would want to open your email?

In a timely email sent one week before the Academy Awards ceremony, Bergdorf Goodman’s subject line offers subscribers red carpet secrets. The email message includes product offerings that align with each of the stylist’s tips.

Make them an offer they can’t refuse
In other words, make it uncomfortable to procrastinate. When appropriate, include urgency terms and deadline dates to compel subscribers to open messages. Return Path’s report on The Art and Science of Effective Subject Lines analyzed how the most common keywords used in subject lines influence performance and found overall that “urgency” subject lines performed the best in terms of read rate.

American Red Cross effectively created a sense of urgency promoting a one-day gift match in this email subject line. Just don’t overdo it. Overuse of urgency keywords in email subject lines will cause subscribers to tune out.

You talkin’ to me?
Use the subject line to tell recipients why the email matters to them. Also, be relevant. Incorporate popular search terms for your brand or business that are relevant to the message.

Home furnishings retailer Dot & Bo’s use of a Twitter hashtag in its subject line helped to grab readers’ attention for this Cinco De Mayo promotion sent on May 5th in celebration of the Mexican holiday.

Yada, yada, yada
It’s important to know how to KISS: Keep it Short and Simple. While optimal subject line length has long been debated, Return Path looked at emails received by over 2 million subscribers from over 3,000 retail senders in February 2015 and found that there is actually no correlation between the length of a subject line and its’ read rate. However, that doesn’t mean you can fully ignore how many characters are in your subject line.

A typical desktop inbox displays about 60 characters in a subject line, while mobile devices display only the first 25-30 characters. If your audience is primarily reading your messages on smartphones or other mobile devices, place the offer or call-to-action at the beginning of the subject line for maximum visibility. Consider how longer subject lines may be truncated to avoid misinterpretation and embarrassing mistakes. For example, “Never write us a check again with automatic bill pay” could render as “Never write us a check again” or “Never write us a check” depending on the device.

Get testy
An effective testing regimen is the easiest way to increase response rates by finding out what works for your program, and subject lines are the easiest component of emails to test. A few tips:

  • Have clear goals and a consistent testing methodology.
  • Test only one variable at a time to ensure you understand cause and effect.
  • Run tests multiple times (3 is recommended) to get definitive results.
  • Know your audience and get as creative as you can within brand limits.
  • Develop a continuous testing strategy to keep subject lines fresh and engaging for subscribers across all lifecycle stages.

The truth is out there
So where can you begin? Return Path’s Subject Line Optimizer is a fast and convenient way to improve the performance of your subject lines. It allows you to search millions of subject lines collected by Return Path’s Consumer Network to see trends of high performing subject lines. With a list of the best performing subject lines from across the email universe, you can test your way to subject line greatness!

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