Nailing Email Subject Lines: 6 Psychological Principles to Boost Your Email Open-Rate
Just like Mac and Cheese, marketers and emails are an iconic duo – one with them doesn’t go without another. I mean, technically they do, but if you know mac and cheese, you just know the mac doesn’t cut it without the cheese and vice versa.
According to IFP, the average ROI for email marketing is $44 for every $1 spent. In comparison, paid advertising only gives you $2 on average for every $1 you invest. That’s like comparing a spark to a bonfire.
Additionally, the Content Marketing Institute reports that 40% of B2B marketers claim that email newsletters are the most important tactic in their content marketing strategy. If you know, you know.
Successful email marketing is an art, and your gateway to triumph is a well-crafted subject line. Based on it, your people choose whether to open the email, leave it unread, or, even worse, direct it to the dreaded spam folder.
In HubSpot’s deep-dive into email marketing for startups and entrepreneurs, they state the following:
“64% of email recipients will judge the quality of the subject line to decide whether they will open an email. Additionally, 69% will report emails as spam based solely on the subject line”.
This makes the significance of diligent subject lines as clear as day.
While one size certainly doesn’t fit all in marketing, human psychology makes the commonalities quite traceable.
Fortunately, Dr. Robert Cialdini’s highly acclaimed book “Influence: The Psychology of Persuasion” offers groundbreaking insights into this by exploring the principles behind why people say “yes” to things.
These insights will be the primary guide throughout this post as we leverage them to gain a deeper understanding of how to get more leads to say “yes” to our emails. For optimal results, it will also cover the best practices for writing clickable subject lines that make these emails irresistible.
1) Reciprocity: Setting the Right Tone
Cialdini explains that people have an instinct to return a favor. Thus, when you communicate right in your subject line that you’re bringing value to the table, it becomes difficult to say no to your email.
This can be free webinars about hot topics, templates to enhance their workflow, insightful reports they would be interested in, or discounts or vouchers on special occasions. The ideas are endless, and based on your market analysis, you are the best one to answer what your prospects may be looking for at a given time.
Make sure it’s a sincere gesture, share it generously, and pinpoint the benefits waiting for them when they open your email. When your intent feels genuine, people will naturally want to pay back: They’ll feel more inclined to check your message, interact with you, and engage with your brand if it’s relevant to them.
2) Scarcity: Making FOMO Work for You
Fear of missing out (FOMO) isn’t just a millennial thing. It is, in fact, a powerful motivator for most of us, and that’s the role scarcity plays in influencing other people’s decisions.
Applying this concept to your subject lines mostly implies creating a sense of urgency or sparking a lead’s curiosity that can only be satiated if they open your email.
Time-sensitive offers, exclusive reports or courses, and limited editions are all effective ways to do this. People usually don’t want to miss out on those things. Even if they aren’t particularly interested in them at the moment, it will at least compel them to crack open your email to know what’s inside.
For your subject line, decide on the right power words to intrigue your leads and stir up inquisitiveness. You’ll see for yourself how your email open rates soar.
3) Authority: The Art of Building Trust
Guess what's hotter than a summer barbecue? Data.
Your recipients need to know you’re a big deal; because you are, and using self-evident data to show that is an absolute game-changer.
If you can draw on a recent study that backs up how awesome your product is, great. If you can jazz it up with real-life examples, testimonials, or case studies, even better. This helps the reader visualize how your product could work for them, showcases your expertise, and builds trust.
Cialdini explains that people are inclined to follow the guidance of those they believe possess knowledge or skills in a particular domain, and they’re much more likely to comply with requests from those they deem trustworthy. That’s what authority is all about.
Especially in B2B email marketing, great email subject lines are those that draw on the brilliance of your offering and back that up with accurate data that lets people know what they can justifiably expect from your business.
4) Consistency: The Finesse of Dispelling Doubt
Human beings are suspicious creatures. Princeton researchers found out that we make up our minds about someone in literally one-tenth of a second. In terms of email marketing, it’s your subject lines that get the spotlight, and you want to choose wisely the impression that you’d like to make.
A crucial principle from Cialdini’s book to keep in mind here that can make this less nerve-wracking is consistency and commitment:
People on your email list have already given you over their data, opting in to receive communications from you, and that’s a good sign. The bad news is that more often than not, they might have forgotten they did until you land in their inbox again.
To make sure you make an applause-worthy landing, think of every subject line as your first to stay committed to delivering value, maintaining quality, and ultimately drawing people in.
In other words, don’t take your prospects for granted by setting the bar high at first, only to end up leaving them with a bunch of irrelevant, spammy emails and subject lines later down the line.
Instead, hold your ground in terms of quality and consistency, even if the open rates are frustrating at first. Over time, this is how people will feel more inclined to engage with you.
5) Likability: Building Connections That Click
People say yes to the people they like, and they naturally gravitate toward those with similar backgrounds, hobbies, interests, and styles of communication. Thus, common grounds are key to successful email campaigns, and there are endless ways to establish them.
A Harvard study found that self-disclosure, for example, stimulates the same areas of the brain as sex and Lindt’s Dark Excellence. They said “good food”, but I think a chocolate bar from Lindt IS good food, don’t you?
That, for instance, was an unintended invite to some kind of self-disclosure and a good example of what I’m trying to say. By asking personal questions about your prospects and their businesses, and showing genuine interest, you make it more likely to start a fruitful conversation that leads to conversion. I mean, if you’re a Lindt fanatic like me, you probably want to be friends by now. So do I!
With this in mind, you can craft subject lines that make opening your emails downright irresistible. Turns out people love to talk about themselves more than anything, who knew?
Another thing you can do is to mention an event you attended together or a relevant mutual person that led you to send them this email. This makes you seem more familiar to them and compels them to engage with you as such.
6) Consensus: Leveraging Social Proof
Consensus, in simple terms, is the idea that individuals are more likely to comply with a request or adopt a particular behavior if they see others, especially those similar to them, doing the same.
Remember the cool kids at school and how they set the standard for what’s hip? That’s exactly what this is about.
In email marketing, social proof is king, and incorporating that in your subject lines instantly makes it a thousand times more engaging.
According to Social Times, a whopping 92% of consumers put their trust in recommendations from others, even people they don’t know, more than branded content. The survey also reveals that 70% consider online reviews as their second-most-reliable source of information. Additionally, almost half of U.S. readers make a habit of regularly checking blogs to stay in the loop on various trends.
In short, people trust other people. That’s why letting your recipients know that other people trust you makes it more likely for them to trust you, as well.
Got a splendid testimonial to share? Can you provide a real-life story of how your product changed someone’s life? Did your services help take a business to new heights? Let your subject line speak for it.
Best Practices for Writing “Clickable” Subject Lines
Now that you have the psychology in your bag, here are some top tips to keep in mind while crafting that swoon-worthy, spellbinding, awe-inspiring subject lines (obviously, I like to dramatize things sometimes) that get ‘em open-rates surging.
Keep it real and personal
Dale Carnegie said it once:
“Remember that a man’s name is to him the sweetest and most important sound in the English language.”
That’s the easiest key to a more personalized subject line.
We all have an emotional connection to our names, and it’s backed by solid science. A study conducted by Marketing Dive states the following:
“Non-personalized subject lines had open rates of 14.1% compared to 21.2% for emails personalized with names and 22% for emails with another type of personalization.”
Of course, personalization goes way beyond using your subscribers’ names. There are other data you can use to make sure your subject lines are truly tailored. This can be their position in the company, their goals, or their pain points.
Another fruitful tactic is to tap into topical conversations that emphasize the timeliness, and thereby relevance, of your message. Reference a piece of content your lead just shared or acknowledge a project they’re currently working on.
In short, let people know you’re actually speaking to them, and keep it real as you do. If you have multiple buyer personas, make sure to use different subject lines to address them accordingly.
Make it short
In a fast-paced digital world, brevity is key.
Long email subject lines are often viewed as a sign of lower-quality email content.
Besides, two-thirds of all email opens happen on mobile devices, which have much smaller screens than a PC. This means that subject lines longer than 50 characters (4-7 words) are cut short. Hence, according to ActiveCampaign, it is recommended to keep your subject lines within this length.
Remember, less is more. So, the shorter your subject lines, the better your chances of increasing your email open-rate.
Let numbers do the talking
Especially in B2B communications, people want to know you’re not just throwing around big words for kicks. Numbers are an optimal way to prove you aren’t. They also tend to impress.
With precise data at your disposal (at least it should be), you can easily let your subject lines speak for your credibility. Let those digits do the talking and watch your open rates skyrocket!
Put the good part first
Incorporating your keywords or most important and engaging information at the beginning of your subject line is a boss-level strategic move in email marketing. It immediately signals relevance, sets the right expectations, and helps people identify value right away as they scan through their emails.
So, instead of beating around the bush, save their time and let your recipients know what you’re talking about in the first couple of words. Thank me later.
Elicit the right emotions
The last thing people want when checking their inboxes is to feel duped by irrelevant offers. To achieve optimal results, you need to establish trust and a sense of reliance instead.
Infusing your subject lines with power words that elicit these emotions drastically increases the probability of recipients opening your email. For example, if you’re writing a B2B email, you could use words like “proven”, “scientific”, or “accredited” to signal reliability. To position yourself as an authority, go for words like “leading”, “pioneering”, or “influential” when suitable. You get the idea.
Simply put: Ask yourself how you want your reader to feel reading your subject lines. Then, be specific in your answer and work from there.
No spam, please
Words and phrases like “limited time” and “exclusive deal” trigger spam filters. Steer clear of these to prevent being reported or landing in the spam folder right away. You certainly don’t want your email to end up being deleted along with emails from John Mick telling your recipients he can’t believe he just saw them in that scandalous linked post.
Yes, I said power words in the previous section, but there’s a fine line between power words and spam triggers. Thanks to AI tools, you can always get a detailed analysis of the “spamminess” of your subject lines. They’re mostly the kind of words that make your email look shady and fishy, think “click here”, “sign up now”, or “risk-free”. Hubspot and Automational also provide extensive lists of such words. However, conducting a Google search for an industry-specific list can be more beneficial.
Ask solid questions
Questions capture your readers’ attention and often encourage a response. When done correctly, using them in your subject lines can up your recipient’s curiosity and leave them wanting to learn more.
A good example of this is using a question that challenges the recipient’s assumptions or common knowledge, such as, “Do you still think a 10% open rate is good?”
If this successfully stirred up your curiosity (yay!), you have your answer to the significance of solid questions, and you can read more about good open rates here.
Use emojis carefully
Emojis are a fun way to add some pizazz to your subject lines. They can also help amplify the emotions you’re trying to elicit. However, there are a few things to keep in mind if you decide to add them to your subject lines:
You should use no more than one emoji at a time.
Make sure they accurately supplement your words.
Different operating systems render different versions of emojis, so you may want to test that first.
Test and iterate
Different email subject lines will work better for different audiences, and using A/B testing is the best way to figure out what works and what doesn’t.
Skipping this part causes you to miss out on crucial insights that can maximize the effectiveness of your email marketing efforts. According to Litmus, A/B testing of email subject lines and content can drive up to 28% higher ROI.
The Summary: Email Open-Rates and The Cocktail Party Effect
Picture yourself at a bustling cocktail party where so many people are talking to you all at once. What would you hear? Noise, exactly. However, if out of all these people someone says something important to you, the other voices are likely to fade to the background while you pay attention to what they're saying.
In psychology, this is called the cocktail party effect, and it demonstrates the idea of selective attention. Our brains naturally gravitate toward what intrigues or benefits us - just like at that crowded cocktail party.
Applying this to email marketing especially while crafting your email subject lines allows you to cut through the noise, capture people’s interest, and prompt fruitful engagement. Simple enough, right? Wrong. But it’s quite doable given everything we’ve covered in this post.
With all of this in mind, if you’re looking for examples of solid subject lines, I would recommend going through Hubspot’s list encompassing 157 of the best email subject lines they’ve ever seen. It’s pretty inspiring.
So, are you ready to be the life of that email party?
