Your customers (and your potential customers) are consistently bombarded by email. The key to getting those customers to open, click and engage with your emails is to make it worth their while, beginning with optimizing your email subject lines.

According to a Radicati study:

  • In 2015, the number of emails sent and received per day was more than 205 billion.
  • The amount of consumer email continues to grow mainly due to its use for notifications (e.g. for online sales) rather than simply as an interpersonal communication tool.
  • In 2015, the number of business emails sent and received per user per day totals 122 emails. That is split between 34 sent and 88 received. Of those 88, 12 (almost 14%) are usually spam.

That’s a lot of noise and clutter in your customer’s inbox. That’s why it’s critically important your message sticks out from the rest – and doesn’t look like spam.

Examples of boring email subject lines

These email subject lines are selling much the same thing, in much the same way. Boring.

Why are email subject lines so important?

Because a high open rate usually leads to more engagement, which, in turn, can lead to new business or customer retention.

However, recipients need to willingly open your emails before then can take action – this is where the importance of subject lines comes in. You want to be able to convey your message without giving everything away, but you also want to be able to convince your recipients to spend time on your email and connect with your product / service offerings.

Three tips for success:

1. Keep your subject lines short – unless longer ones test better.

In 2015, Return Path analyzed 9,313,885 emails to discover which subject line length is most effective.

2015 Return Path study on email subject line length

In MarketingSherpa’s blog post about this, they quote Tom Sather, Senior Director of Research, Return Path: “… ‘average read rate’ is defined as ‘the percentage of email recipients who have marked your email as ‘Read’ in their email client [i.e. email reader] — typically thought of as more accurate than open rate, since read rate is not dependent on image downloads.’” The data says:

  • The most frequent length of characters is 41 to 50 characters. One reason this is considered a best practice is that many email readers and browsers cut off subject lines longer than this, and mobile devices are even more limiting.
  • But note that subject lines of 61 to 70 characters had a 17% average read rate, the highest of any length.

Do you know your email recipients well enough to know how they read your emails? If you do, and if they’re reading email mostly on mobile devices, then double down on shorter subject lines. For further reading, here are 10 best practices for mobile-friendly emails.

So, the takeaway is: Shorter is usually better, but if you’ve got a longer subject line that you like, test it. Front-load the key words so you’re sure they get seen.

Every email send is unique, and your mileage may well vary.

One additional way to learn how to write compelling subject lines is to take a look at what NOT to do. Sounds like an Act-On blog post, right? It was. Read 8 terrible email subject lines.

2. Keep your subject lines on topic, and not misleading.

Remember that your subject line is setting expectations for the content of your email. Nobody likes bait-and-switch. You want to ensure that your subject lines get your message across succinctly, without misleading the recipient. If a recipient thinks a subject line is misleading, they could feel that they’ve been duped. This could get your email marked as spam by an angry reader (they could be a former customer, or could have just had a bad day). People sometimes make this mistake when they’re riffing on a current news topic or trying to be funny. Don’t sacrifice clarity for cleverness.

And don’t use RE: or FW: to make it look like the email is part of a string the recipient has been previously involved with.

3. Personalization can be key.

In Q1 2015, Experian performed a custom analysis for MarketingSherpa based on Experian Marketing Services’ quarterly email benchmark analysis from client brands within the United States and Canada (which relies on clients that opt in to participate in this study). The results:

Q1 2015 Experian email personalization study

  • Across all industries, including a name in the subject line bumped open rates by almost 30%
  • Consumer products and services realized the greatest bump (almost 42%)
  • Business products and services realized a 13.3% gain, which is much less than consumer products, but is still a highly desirable outcome for B2B companies

The study points to even greater gains in transaction rates and revenue per email.

Geography: If it makes sense, localization is an aspect of personalization that works really well.

localization in the email subject line

In the email above, the recipient will realize instantly that the event is being held in her city, making it potentially more interesting … and making the email more worth opening.

Testing email subject lines

Using these tips can help get your emails opened, increase engagement, and get your message across to your target audience. But your business is unique, and so are your buyers. Your gut instincts may have been right on all last year, but things change, and you want to stay in front of changes. Learn about A/B testing.

Your checklist for email subject lines:

  1. Know your audience, and optimize your subject line for the mobile inbox first if that’s what they use
  2. Clear subject lines are the name of the game
  3. Be relevant
  4. Personalize if you can
  5. Localize if you can
  6. Consider using a number, such as “55 ways to get your emails opened.” Lists still work
  7. Test, test again, and optimize. Always be testing, and trust your results
  8. Check out what your competitors do. Don’t copy, but be aware, and test your own versions
  9. Make it actionable if possible. People typically delete more emails than they open, so the more reason you give them to open yours, the better your rates should be

Set yourself up for success by crafting, testing, and adjusting subject line content based on audience reactions and calls to action that really drive your point home.

Want to be really, especially, wondrously, amazingly adept at subject lines? Download our 12 Tips for Amazingly Effective Email Subject Lines.

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