The Psychology Of Emails: How To Write Subject Lines That People Can’t Ignore
Do you want to receive higher open rates from marketing emails?
Email marketing can be a tricky form of marketing to master since your emails sit between marketing message after marketing message, not to mention personal emails and any other type of emails your reader receives.
In this post, you will learn how to use psychological triggers to encourage your readers to open more of your emails.
1. Change the tone of your subject line depending on the purpose of your email
Sometimes you don’t need to be clever or compelling. You just need to be sincere.
Try changing the tone of your subject line depending on the message your email is meant to convey:
- Informational
- [new feature] is coming to [app name]!*
- Urgent
- Registration closes in 24 hours!
- Personal
- Thanks for signing up, Roy!
*Insert your own text in these brackets.
2. Include keywords
Keywords aren’t only meant to appease search engines. They also define topics your target audience finds important.
If your email covers a topic you know your audience cares about, include keywords related to it in your subject line.
Use a keyword research tool to find keywords for a particular topic.
3. Use brackets to emphasize offers and calls to action
While you should avoid using overused marketing words like “free” and “buy now,” you should still include calls to action in your subject line when they exist in your email.
When you do, use brackets around them to emphasize them:
Example: [Gift inside] Grab a t-shirt at a reduced price
Here’s a real-world example from Sprout Social:
[Invite] How to bring the social data receipts
4. Utilize the FOMO phenomenon
FOMO stands for fear of missing out. It’s a phenomenon attributed to social media that describes the feeling that arises in social media users when they view something on social media they don’t have.
You can use your email subject line to trigger this emotion in your readers.
Here’s an example from Bunny.net:
Almost showtime! Join us for the LIVE demo and learn how to deploy Magic at the edge!
Their subject line emphasizes how the demo will be starting soon, which means readers have a limited amount of time to decide to attend.
Here’s another example from SurgeGraph:
This event will be ending in 48 hours!
You can also use this technique to tease a sneak peek or imply negative outcomes the reader will experience if they choose to ignore your email.
Example: Don’t miss out! We won’t print these [product] in the future!
5. Include power words
Power words are one of the most effective ways to increase clicks on headlines and open rates alike.
Power words are emotionally-charged words that trigger emotions in your readers.
Here’s an example from Kinsta:
Discover improved navigation and PHP tools at Kinsta
“Discover” is a power word meant to trigger curiosity in the reader.
Other examples of power words include unlock, master, ultimate, guaranteed, exclusive, proven, featured, now, new, fresh, limited, critical, essential, outdated, devastating, painless and first look.
6. Use clever phrases to promote something
If you’re trying to promote a product, try emphasizing a benefit it offers by using a clever phrase in your subject line.
For example, if you’re promoting a metal reusable straw you offer, use something along the lines of, “This is your final straw” as your subject line.
7. Ask questions
Try including a question in your subject line to drive curiosity or trigger a specific emotion.
Here are a few examples:
- Curiosity
- Do you know what happens to your car if it runs out of oil? We tested this
- Emotion
- Are you satisfied with the amount of money you have in your bank account right now?
Try to convey the same emotions with your subject lines for your own niche.
8. Start off with a hook
The first word or element of your subject line should be compelling.
You can see how some of the examples in the screenshots above use emojis, such as the police car light emoji or the fire emoji.
This is intentional as it catches the reader’s attention as they browse their email. You can do the same with power words and calls to action in brackets.
9. End with a cliffhanger
Just as you can begin your subject line with an attention grabber, you can also end it in a way that makes your reader want to open your email to find out what’s inside.
The cliffhanger technique involves interrupting your subject line with three dots so that your reader needs to read it to learn more.
Example: The first thing I do when I get a new guitar is…
10. Use parentheses to include small notes
Parentheses are a nifty little tool you can use to keep things professional in the main part of your subject line and casual afterward.
Example: 3 exercises every skateboarder in their 40s needs to do (I’m not kidding)
11. Include statistics to grab your reader’s attention
If your email or what you’re promoting has a statistic, include it in your subject line.
Just don’t use currency symbols or the percentage symbol. These characters get flagged by spam filters often.
Example: Email subject lines that have between 61 and 70 characters have the highest open rates
12. Use numerals when writing numbers
Remember, your email needs to stand out among all of the other emails your reader has in their inbox.
So, when you include numbers in your subject line, include them numerically instead of writing them out.
Example: 5 ways to boost your immune system this fall
Not “Five ways to boost your immune system this fall”.
13. Put important words in all caps
While you shouldn’t put your entire subject line in all caps because it’ll cause your email to be labeled as spam, consider putting power words in all caps.
Example: 10 study techniques to help you MASTER your midterm
This draws your reader’s attention to emotionally-charged power words.
14. Use sentence case to appear more casual
Sentence case is a grammatical style for titles in which the first letter is capitalized but everything else, except for proper nouns and similar important words, is in lowercase.
Again, your reader’s inbox is filled with marketing emails. You can really stand out by approaching them with a more relaxed marketing style.
Here’s an example from Metricool:
Save time creating quality content with Metricool
Not, “Save Time Creating Quality Content with Metricool”.
15. Use emojis to spruce things up
Several of the real-world examples I’ve given use emojis, and you should, too. Sparingly, of course.
You want to appear cool and aloof, not desperate to fit in with the younger crowd.
Use relevant emojis in your subject lines sparingly to increase your odds of grabbing your reader’s attention.
An emoji can really stand out among all of the text in their inbox.
16. Reference trends
When we say “reference trends,” do we mean mentioning something that happened at the Oscars?
Probably not, but you should reference trends and hot topics in your niche or in adjacent niches.
Example: X is removing their block feature, but we’re beefing up moderation
17. Use simpler, consumer-focused language
Let’s say you reviewed a particular product, and you want to promote the video to your email list.
Don’t use a subject line like, “Bluesky has all of the microblogging features you need without the overhead.”
Use “How to microblog without handing your data over to a mega corporation” instead.
This places the focus on your reader rather than the product you’re promoting.
18. Include locations
Sometimes the problem with marketing messages is that they might not be relevant to your reader.
If you host events or own local businesses, include the locations in your subject lines.
Example: Join us for a LIVE demo in Seattle!
19. Keep things concise
You know that statistic we cited earlier? About subject lines that have between 61 and 70 characters having the highest open rates?
That was real.
Your reader’s attention span is shorter than it was a decade ago. Plus, they have a lot of emails to sift through.
Have mercy on them, and keep your subject line as short and to the point as possible.
20. Make sure your copy satisfies your reader’s curiosity
The last thing you want to do is engage in clickbait. It’ll only lead to your subscriber unsubscribing from your email list.
Prevent this from happening by ensuring your subject line accurately represents the copy in your email.
21. Get more creative with email digests
Let’s say you publish a regular email digest for the latest news in your niche. Don’t use the same subject for each new email in the digest.
Don’t number them, either.
Grab a compelling headline from the digest, and use that as your subject line instead.
22. Insert your brand name in the from field
Your reader subscribed to your brand, not the individuals within it.
Always use your brand name in the From field. Do not have your marketing team use their own personal names in this field.
Only use your name when your name is your brand name.
Final thoughts
Marketing emails are difficult to get right but with the tips we’ve covered above, you’ll be able to get more subscribers opening your emails than before.
Just remember that the tips above are best practice. And that should only ever be your starting point.
This is because what works for one audience doesn’t always work for another. Sometimes you may need to tip convention on its head.
So, I’d recommend running some tests. Most email marketing tools will have some way of doing this. For example, with MailerLite you can A/B test your subject lines and other parts of your emails to find out what works.
Based on data. No guesswork.