How Not to Mess up Your Email Subject Lines

How Not to Mess up Your Email Subject Lines

In 9 Helpful Tips to Enjoy the Benefits of Email Marketing, I showed you that email has a median ROI of 122%, which is more than four times higher than other marketing formats examined, including social media, direct mail, and paid search. In this blog post, you will learn how not to mess up your email subject lines so that people will actually open your emails and read them. First, you will find 6 types of email subject lines you should avoid. Then, you will find 7 tips to optimize your subject line and finally, 20 creative email subject line example templates are listed.

‘How Not to Mess up Your Email Subject Lines’ In this blog post, you will learn how not to mess up your email subject lines so that people will actually open your emails and read them. First, you will find 6 types of email subject lines you should avoid. Then, you will find 7 tips to optimize your subject line and finally, 20 creative email subject line example templates are listed. Find them here:

6 types of email subject lines to avoid (and what to try instead)

Kasia Kowalska has found out that these six types of email subject lines should be avoided:

1.      Email subject lines with words that trigger SPAM filters

The death knell of any email is when it gets caught in a SPAM filter. If your email gets caught, the chances that your prospect will open and read your email drops to virtually zero. One great step is to look up lists of words and phrases that commonly trigger SPAM traps and to ensure you have not included any. This will vary depending on your industry but a quick Google search will turn up the biggest culprits.

2.      Email subject lines that ask for time

Time is the only finite resource. We cannot make more time. So, when someone bestows their time to you, it is a precious gift. Keep this in mind when drafting email subject lines and try to avoid asking them for anything. This is especially true for cold emails. Your prospect does not know you and does not (yet) care what you can do for them. Until they understand why you are contacting them, any request for a meeting or call will feel like a chore. Email subject lines to avoid like this include “Do you have 15 minutes?” or “Can we have a quick chat?”

3.      Email subject lines that have typos

Typos look sloppy and unprofessional. If you are not taking the time to run a spell check before pressing ‘Send’, your prospects might wonder what else you will cut corners on. As I mentioned in 20 Powerful Google Chrome Extensions for Entrepreneurs, Grammarly is a great extension that checks your spelling on emails and websites as well as in MS Word.

4.      Email subject lines with your company name or branded terms

This comes down to clarity. Chances are, your prospect has not heard your company’s name before. If they are not familiar with your company or branded terms, this will just create confusion. You want the value of your email to be immediately apparent. You do that by putting the customer first. Use language your prospect will understand.

5.      Clickbait email subject lines

Just like with video or article titles, you should not put ‘clickbait’ in the email subject lines to avoid category. A common tactic among digital marketers is putting “Re:” at the beginning of the subject line. This works by tricking a prospect into thinking there is an existing conversation. Essentially, you want to avoid email subject lines that entice your prospect to click for the wrong reasons.


Caps lock is the digital equivalent of yelling. While it might make an email standout in an inbox, it is not in a good way. Using exclamation points falls into the same category.

7 tips to optimize your email subject line

Nathan Ellering lists the following 7 tips you can use to optimize your email subject line:

1.      Leverage words that have been proven to boost email open rates

His research into email subject line mechanics dug up 100 words, terms, and symbols that are highly likely to influence open rates when you use them in your subject lines. You can find them here. Further analysis suggests you will get the best open rates by using 3 or more of the words/terms and/or symbols from that list in your subject line.

2.      Remove words that reduce open rates (or trigger spam filters)

As mentioned above, just as there are words that typically increase email open rates when you use them in subject lines, there are words that negate those opens, too. Here is a shortlist of 100 words, terms, and symbols to avoid using in your email subject lines. It is best to use zero of these words, terms, or symbols in your email subject lines.

3.      Include a number in your subject line

Including numbers in blog post headlines increases clickthrough rates by 206%. It turns out, like blog post headlines, using numbers in your email subject lines increases email open rates. A recent study from YesWare that analyzed 115 million emails suggests email open and reply rates are higher when a number is present in the subject line.

4.      Put an emoji in your subject line 😊

Campaign Monitor recently researched the use of emojis in subject lines to understand if their inclusion increased open rates. Apparently, brands that are using emojis have seen a 56% increase in their unique open rates. Campaign Monitor is really seeing an increase in emojis, and you can use them as a brand appropriately, and they do add a nice little bit of flare and attention-getting in the inbox. Best practice suggests using 1-4 emojis in your subject line will boost your email open rates.

5.      Write the best length email subject line: 17-24 characters

While studies differ drastically on the topic of email subject line length, there is some general best practice advice throughout: keep your subject lines short. The reason for this is 50% of all emails are opened on mobile devices. iPhones show about 35-38 characters in portrait mode, and Galaxy phones show roughly 33 characters in portrait mode. Long story short: Make sure the 50% of your subscribers who will open your email on their mobile device can actually read the entire subject line.

6.      Make your email subject line 3-5 words long

Studies suggest the more words you use in your subject line, the fewer opens you will get. Best practice is a short number of characters and a short number of words.

7.      Test title case subject lines

YesWare’s research into 115 million emails suggests that subject lines in title case are most effective at boosting your open and reply rates. That study suggests the psychological reasoning behind title case’s success is perceived authority: even something as small as using title case instead of sentence or lowercase in an email subject line is an authority badge for the sender.

20 creative subject line example templates

Ellering offers you the following subject line templates as a type of “swipe file”: copy, paste, and then fill in the blanks to get started.

  1. Stop {Undesirable Emotion} Now
  2. {Desirable Outcome} (Your First 3 Steps)
  3. New {Thing}: What It Means For {Audience’s Role}
  4. What {Credible Influencers} Are Saying About {Topic}
  5. {Someone Audience Looks Up To} Can Afford Any {Product}, She Uses…
  6. Best {Emoji} + {Emoji} + {Emoji} = {Emoji}
  7. {Topic}, {Topic}, and {Seemingly Unrelated Topic}?
  8. {Personalized Company Name} + 497% More {Need} = {Emoji}
  9. {Emoji} Your {Emoji} With…
  10. {Personalized Name}, Earn {Something Desirable} Today Only
  11. You’re Missing Out On {Something Desirable}
  12. Tonight Only: A {Audience’s Role}’s Dream
  13. Want 587% More {Something Desirable}? {Emoji}
  14. This Is A Sales Email {Emoji}
  15. Don’t Forget! {Event} Today {Emoji}
  16. …When You’re Sick And Tired Of {Something Undesirable} {Emoji}
  17. “{Quote}”
  18. A {Topic} Process To Reduce 30-50% Workload {Emoji}
  19. {Topic} + {Topic} + {Topic}
  20. “I Love {Something Undesirable}!” (said no one ever)

Start with email marketing

You now know the benefits of email marketing and how to get started. If you want to send out your emails or other content in more than one language, I might be able to help. I am a translator (Dutch <> English), so contact me at if you want more information.

Alternatively, if you are looking for more resources on email marketing, these books may help you. Also, this blog describes how current digital marketing trends can help the entrepreneur. And while you are at it, sign up for my newsletter to receive a notification when I publish another blog about marketing, entrepreneurship or translations!