How to Write the Perfect Email Subject Line [Infographic]

writing the perfect email subject line

This is day 4 of our “Smart Email Marketing Conversion” week, make sure you keep coming back to catch the rest of the posts, and check out the ones from earlier in the week.

Let’s start off with one of the things everyone wants to know, the dos and don’ts of email subject line writing.

Set your subscribers’ expectations and clearly state what’s inside the email
Write your subject lines like advertisements. The folks at MailChimp say it perfectly: “When it comes to email marketing, the best subject lines tell what’s inside, and the worst subject lines sell what’s inside.”


Why do these things matter? Well, the average business person receives 121 emails a day. I know that personally, on the commute to work every day, I delete 90% of them, so that my inbox is more digestible by the time I get to work.

In short, there’s a lot of crap out there. And despite the promise we all tell ourselves to unsubscribe from all of the emails you don’t want to receive, some companies make you jump through hoops to do this, which is discouraging at best.

So how do you cut through the clutter and make sure your email isn’t one of the ones that get’s dumped right away? Easy, you write a perfect email subject line. Sure, it’s that easy.

Writing an effective subject line is one of the hardest parts of email marketing. The infographic explore some ways to do this, so first I’ll summarize fundamentals before getting into a 6-step checklist for your next campaign.

1. Don’t be afraid to use the following:

  • ALL CAPS (not for the whole subject line, just to hight the occasional word)
  • The word FREE
  • An exclamation point!

2. Use geo-location to increase personalization.

3. Frame your subject line as a question Target the question at the types of problems your customers/leads need answers

4. Keep it short: 50 characters or less works best. According to MailChimp, 28-39 had the highest click rate in a study of 200 million emails.

5. Don’t use the following chintzy tactics:

  • Symbols and special characters: they might get people opening them out of curiousy, but them make you look cheap
  • Cheating: don’t used FW: in your subject to imply it’s come from a trusted source
  • Scams: People have become wary of requests for help
  • Numbers: details of your special offers (50% off etc.) can be useful, but don’t overuse them or you’ll establish yourself as a sales merchant
  • Names: Using first names in the subject line can reduce open rates

Now that we’ve covered the fundamentals of to do and what not to do, here is a 6-step process to improve your open rates:

6-Steps to Improve Email Open Rates

  • Step 1: Be useful and ultra specific – make sure it’s relevant and useful for your customers
  • Step 2: Identify yourself – mention your most identifiable brand product in the subject line, or prefix the subject line with a consistent identifier
  • Step 3: Be visually different – make you subject stand out visually by trying square brackets, sparing use of capitalization, phone numbers or quotes
  • Step 4: Use timely topics and urgency that are top of mind, and use urgency occasionally to point out deadlines
  • Step 5: Use a call-to-action (CTA) by asking a question
  • Step 6: Test your subject lines so you can repeat what works best

If you have any other tips that you found to work, please share them in the comments below.

how to write the perfect email subject line
Infographic by – Click for full size version.

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About Oli Gardner
Unbounce co-founder Oli Gardner has seen more landing pages than anyone on the planet. He’s obsessed with identifying and reversing bad marketing practices, and his disdain for marketers who send campaign traffic to their homepage is legendary, resulting in landing page rants that can peel paint off an unpainted wall. A prolific international keynote speaker, Oli is on a mission to rid the world of marketing mediocrity by using data-informed copywriting, design, interaction, and psychology to create a more delightful experience for marketers and customers alike. He was recently named the "The 2018 Marketer to Watch," in the under 46 category, by his mother.
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