Use Psychology To Increase Email Open Rates

Alicia Doiron
July 16, 2021
minute read

23 unread messages.

That’s what my inbox says right now. Every day I open my email to an overwhelming amount of new messages. If you’re like me, a marketing email needs to stand out for me to open it.

I have my email divided into three categories: primary, social and promotions. After taking care of business I like to take a glance at my promotions to see if there are any goodies that catch my eye. After scrolling through, I usually find one or two emails that look intriguing and you know what, all of them are using psychology to get me to open them.

I’m not talking about any sort of crazy mind tricks, although, wouldn’t it be nice if a hypnotist’s pendulum popped up and convinced your customers to buy your product? The good news is, these techniques are just as easy and effective. No gimmick, just real psychological triggers that are guaranteed to increase your email open rates.


Dale Carnegie, author of How To Win Friends and Influence People, says that “using someone’s name is incredibly important” and that “a person’s name is the sweetest sound in any language for that person.”

In the last few years Starbucks started asking people their name to put on their Starbucks cup. The amount of people getting upset that their name was spelt wrong is incredible. There’s actually a website dedicated to this monstrosity seen here.

While using someone’s name is important, there is much more to personalization than that. Take for example this case study from Marketing Sherpa. HomeAdvisor was able to double their conversion rate due to personalization by focusing on sending very personalized emails.

When customers on the site are looking for remodelling service professionals, they fill out HomeAdvisor’s form. When they click ‘Submit,’ they are matched to three or four different remodellers to get estimates, and then three different personalized emails are sent out.

The first email has the subject line, “Remodelling Costs in [City]. How Much Should You Expect to Pay?”

The second email’s subject line is, “Architects: Your most important remodelling step,”

The third email’s subject line is, “Fantastic Flooring: What to choose and why,”


Why do these emails work? Because these emails were sent only to those customers who took the time to fill out the form on remodelling. They  all contain information that someone who is remodelling their home would want to know.

We all want to feel special and when we receive emails that are specific to our interests we are much more likely to open the email.

I’m signed up to many different stores newsletters and I find myself unsubscribing all the time because of this, even if they use my name. The email still needs to be relevant to what I like. I’m not the only one who feels this way either. In a survey from Hubspot, 38% of the survey takers said that they signed up for a company newsletter hoping to receive information that is relevant to them.


People are sick of receiving information that has nothing to do with their interests or likes. However, sending targeted, personalized email will have people opening up your emails faster than you can say abracadabra!


As someone whos favourite actors include Jim Carrey, Steve Carrell and Will Farrell, this one is extremely important to me. Everybody loves to laugh, it’s the physical part to humour. There’s a reason why “they” say laughter is the best medicine. Laughter relaxes the whole body, boosts your immune system, decreases stress hormones and releases endorphins, the body’s natural feel-good chemicals. It also plays a powerful bonding role between humans.

According to Helpguide humour and playful communication strengthen our relationships by triggering positive feelings and fostering an emotional connection. When we laugh with one another, a positive bond is created. It’s also believed to be an effective tool for keeping relationships fresh and exciting. Which is what a lot of email subject lines aren’t, exciting.

Most email subject lines are SO boring. I cannot tell you the amount of times I’ve seen a subject like “10% off today just for you” Wow really, 10%?! Just for me? You can do better than that. That’s not to say that sales don’t work, they do. But, when someone like myself receives an email like this from 20 other companies, you blend in and now your email is getting a 1-way ticket to my trash.

Be funny! It doesn’t matter if you’re a company that sells tools, clothing or food. If you want people to feel an emotional connection with you, use some humour. Be original. Convince them they weren’t wrong for signing up with you in the first place.

Design By Humans does a great job of using a bit of humour and personality. A while back, I received an email with this subject line:

These Tees Will Scare Small Children + Weekly Shirt Giveaways!

Modcloth is another example of a company using humour and quirkiness to grab their customers attention and stand out. Here’s a screenshot of what I saw in my inbox:



I recently talked about urgency and how it can increase conversion rates for your online store. Well, the same principles apply to your email subject lines. You want your customers to act fast and nothing does this quite as good as urgency. Things like “act fast” and “offer ends tonight” are all great ways to propel your customer to action.

Heres a real life example from Old Navy that caught my attention.


Urgency when coupled with free, which I will talk about next, is an extremely powerful duo.


Free is one of the most powerful words in the English language. People love free stuff. At Costco, I’ve actually witnessed people running towards the free taste tests (I may or may not have been beside them). It’s hilarious how people will react over a free piece of pop tart. Free makes people go a little bit nuts.

In his book, Predictably Irrational, Dan Ariely explains the impact free has on us. He ran multiple experiments and the outcome was consistent. When people were faced with options, the free option was almost always chosen.

Ariely explains “With the opportunity to receive something for free, the actual value of the product or service is no longer considered.” He goes on “Most transactions have an upside and a downside, but when something is free we forget the downside. FREE gives us such an emotional charge that we perceive what is being offered as immensely more valuable than it really is.”

According to Adestra’s 2013 Email Subject Line Analysis Report using the words “free delivery” in a subject line will lift open rates by 50.7% But, before you get all “add free to anything and everything” proceed with caution.

Just a word of caution: when using the word “free” in email subject lines, you need to be careful as it can make the email look spammy. You see, people only like free stuff when they feel there’s a good reason for it. The Cosco taste test lures you into buying the whole box so, fair exchange. Free shipping works because people reason, “well I bought the product so free shipping should be included.” If there’s no fair exchange, people may start to question whether this deal is too good to be true.


Humans are curious creatures by nature. When we were kids we would often get into trouble due to our curious nature. Everything was new and we wanted to experience everything. As adults we’ve acquired quite a bit of knowledge but still have that thirst for more. We love to ask questions like why do we exist? What is consciousness? Why won’t Kim Kardashian just go away?

While asking a question to your customers is a good way to peak their interest, it isn’t the only way. Your subject line should wet your customers appetite. You’ll have them asking questions like “what did they mean by that?”

Researchers at Carnegie Mellon University conducted a study to find out why people open certain messages but not others. Here’s what they found about people and curiosity; “participants wanted to open messages when they had moderate levels of uncertainty about the contents. They were “curious” what the messages were about. This occurred when they knew who the email was from but were not sure of its content.”

This points to “the information gap” theory of curiosity which was first developed by George Loewenstein of Carnegie-Mellon in the early 90s. Loewenstein states that “the desire for new information is generated in response to a difference between what one knows and what one wants to know” When people become aware of a gap in their knowledge, they are driven to fill this gap.

Here are some examples right from my inbox. First up, Banana Republic.


What are the three pieces they are talking about and how will this fit into my current wardrobe?

The next is from Whistler Blackcomb.


They ask me a question that makes me want to see what people are saying. What further caught my attention is that there is a video to go along with what I’m assuming are going to be claims that the skiing at Whistler is good.


Like me, many people receive hundreds of emails a day. We’re busy and we don’t have time to comb them all in detail to find the emails that interest us.

We glance at our emails, so in order to catch our eye, an email has got to stand out. These psychological triggers are sure to help you on your quest to increase your business email open rates.

What has worked for you?

Has any of these psychological triggers worked for your business? Which ones? Are there any subject line tactics to increase open rates that weren’t mentioned?

Frequently Asked Questions


Alicia Doiron


Alicia is a freelance content writing maven with over 10 years of experience working in the eCommerce and digital marketing space. When she's not helping businesses slay words and reach goals, she can be found exploring the great outdoors in Melvan – her 82' Westfalia.

Unlock the full potential of your email list