How To Write Email Subject Lines

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How To Write Email Subject Lines

Email marketing seems pretty simple to most business owners. Write regular emails that provide valuable information, promote your products and services, and get sales. BOOM! Easy, right?

Of course, if no one is actually OPENING your emails, all your best efforts are in vein. The most enticing offers will never lead to conversions if you don't have a way of crafting attention grabbing subject lines that people can't wait to click on and open up!

This post will walk you through some strategies and best practices on how to write email subject lines that actually lead to opens and conversions.

1. Opt for straightforward over flashy.

It can be tempting to use flashy, attention-grabbing language to entice opens. But according to MailChimp’s analysis of over 40 million emails (!), straightforward, no-nonsense subject lines vastly outperformed ‘salesy’ ones. Crafting catchy email subject lines doesn't have to be so tough after all! 

Following the analysis of their observations, MailChimp shared their top secret formula for email subject lines: “This might sound dead-simple, but here you have it: Your subject line should (drum roll please) describe the subject of your email. Yep, that’s it.”

When in doubt, keep it simple. Which brings us to #2….

2. Be honest about what is inside your email.

Crafting an irresistible headline is key, but if your content does not deliver on what your headline promised, your subscribers could feel duped.

For instance, a headline like “75% off all products today only” is sure to get opens. But if you are not actually offering a 75% discount, you are going to end up losing the trust of your subscribers…not to mention seeing a significance increase in complaints and unsubscribes.

3. Use power words.

There are certain words that some research has shown increase email open rates. While the researchers behind the study state that there is no ‘magic bullet’ when it comes to finding high-performing keywords, they did find 15 words that seemed to perform better than most.

  • Using your subscriber’s first name (warning: test this one with your audience! I have seen other research that suggests this may not work in all industries)
  • Invitation
  • Introducing
  • We
  • A
  • Your/You/You!
  • Year (for instance, 2015)
  • Update
  • New
  • Month (for instance, March)
  • Special/Specials
  • News
  • Sale/Sale!
  • Events
  • Offer/Offers

4. Subject lines with 6-10 words seem to perform best.

According to research by Retention Science, email subject lines containing 6-10 words resulted in an average 21% open rate.

They also found that 52% of emails sent used more words than this (11-15); meaning that using this strategy may just set you apart from your competition.

5. Increase the relevance of your email subject lines through segmentation.

You are using segmentation for your list, right?

Segmentation is simply sending emails to a certain segment of your list based on a particular factor.

This could be age, gender, location, interest or a number of other factors. The point is that segmentation allows you to send the PERFECT message to each subscriber based on what you have learned about them.

When you segment your email list, you are able to come up with email subject lines that more closely match each segment, leading to higher open rates and conversions.

Here is an example: Let’s say you have an online pet supply store. Without segmentation, you may send an email to your entire list with the subject line, “The Best Products For Your Pet”. With proper segmentation, you can make this subject line more relevant; for instance, “The Best Products for Your Dog”, “The Best Products for Your Cat”, etc. This will give you the best chance at increasing your open rates and conversions.

6. Remember that there are no hard and fast rules for writing attention grabbing subject lines!

These strategies are all great ways to start testing your own subject lines. Just keep in mind that different strategies will work differently depending on your niche, industry and audience. And sometimes, the strangest subject lines can actually be the most effective!

For instance, according to a study done by email management service ContactMonkey, the highest performing email subject line example they have ever seen was…get ready for it…


Yep, that’s it. Just Re:. They once saw an email with this simple subject line receive a whopping 92% open rate.

I’m not saying you should try this strategy, as I’m almost certain it would increase your spam report numbers. However, it does highlight that sometimes trying out unlikely email subject lines can really pay off!

Looking for email subject line ideas for your blog and social media posts as well? Then you might be interested in my post The Ultimate Guide to Writing Social Media Headlines That Get More Clicks.

Have you used any of the strategies above? What types of email subject lines have worked the best for you in terms of opens and conversions? Let us know in the comments below!

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Kim Garst
8 years ago

Crazy, right?

Mark Luice
Mark Luice
4 years ago

It’s a really great article for how to write email subject line. You share a great think that most of the people don’t know. Thanks again.

Solomon Baah
Solomon Baah
3 years ago

I want to grow my Twitter account so kindly follow me, thanks

Solomon Baah
Solomon Baah
3 years ago

I created an account with MailChimp but I couldn’t use it, I don’t have any business to promote but I wanted to direct people to my Twitter account so that they can follow me.

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