Email Subject Lines: The Informal Guide for eCommerce

Posted on February 15, 2019

If you’re operating a website or business, I’m sure you’re using email marketing tactics to communicate with your customers. Are you having success? If not, the problem might be your email subject lines.

You can have the best email campaign in the world, but it’s useless if your customer never opens your messages. Getting the consumer to click your email is half the battle. It all comes down to the subject line.

Don’t think subject lines are important? Think again.

Let’s look at some statistics about the importance of email subject lines.

email subject lines-ecommerce-marketing

If you want to increase opens, clicks, and conversions, you’ll need to master the process of creating perfect email subject lines.

Let’s look at some strategies that you can implement today to increase those open rates and turn email into one of your top revenue generators.


According to a study by HubSpot, email subject lines that build a sense of urgency generate a 22% higher open rate.

The Athletic does a stellar job of this with their email subject line in the following example: “Today Only – Get 50% Off The Athletic

email subject lines-ecommerce-marketing

The subject line creates a real sense of urgency/scarcity. Today Only? That has the potential to create serious FOMO for consumers. FOMO, or fear of missing out, is an always-powerful emotional lever that the rise of social media has only heightened. 

As we’ve previously covered, the poster-child of FOMO, Supreme, and now the 5th, have baked scarcity into the very core of their brands. Study them and implement these tactics in your email subject lines and watch your open rates soar.

“Buy now or forever miss out” is a powerful message.

Make it Personal

Wait. I’m going to hand the mic off here.

The father of copywriting, Gary Halbert has written about this very topic. I would be doing you a massive injustice to write about personalizing email subject lines when he’s already covered this general idea infinitely better than anyone else could. While Gary comes from a time where direct mail was king, these same principles can be applied to email today.

Gary, take over.

“Today, we’re going to concentrate on getting people’s attention by learning how to write what I call ‘killer’ headlines. Hark unto me. Listen: If you want to capture the attention of someone in a crowd, what’s the best way to do it? It’s really quite elementary, My Dear Watson. What you do is… 
You Call Him By Name! 

And, if you want someone riveted to your sales letters, hook up with some outfit that can do Admark or laser printing (or else use your word processor) and put your reader’s name in a headline printed at the top of the sales letter you send him. Like this:

Ben Suarez Attempts Suicide
After Realizing He’ll Never Be
As Good-Looking As Gary Halbert! 

Bill Bonner Fails To Hire The
Prince Of Print And Loses Millions! 

Frank Cawood Cashes In Big
By Mailing Unique
“Concept Letter” Developed By
California Madman!


Jimmy Calano Changes His Will
And Leaves All His Millions
To Guru Gary!


Alicia Evans Expresses Astonishment
At Seeing Her Name In Newsletter
Written By Demented Nerd From Ohio! 

And so on. What I have just described is the ultimate way to get attention in a sales letter. No one, not even someone as blase` as Feeney Griffith, will fail to perk up at seeing his or her name in print, especially if it’s unexpected.”

Check out his full post on writing killer headlines here.

Social Proof

Popularity is mostly based on what we like, not because one product is truly better. We like what others like. We’re fitting in. It’s the status-quo. This doesn’t just reveal our brand affinity, it’s directly influencing it.

Thanks to our newfound cultural dependence on instant gratification and social media, social influence is more powerful today than ever before.

You can use celebrities, micro-influencers, or even your own uncle to portray influence and create a buzz around your brand.

Let’s look at PSD Underwear’s collaboration with Baker Mayfield again.

PSD is using Baker’s influence here to collect emails. You can see how they can easily transition this into their email subject lines.

Some examples of using Baker in their emails could include:

“Baker Mayfield wears PSD underwear?”

“Baker Mayfield seen rocking PSD after big win”

“Move over LeBron. Baker Mayfield’s our guy.”


Humans are inherently curious. Don’t tell me everything you want me to know in your email subject line.

Tease me.

Let’s say your subject line is, “25% off Sweaters. Shop Now.”

Why would I open that? I’m not curious. I am not really in the market for a new sweater. I don’t really care to open your email. You’ve told me everything I needed to hear in the subject line. Rather, pique my curiosity. Make me feel like I have to open your email.

“Our CEO HATED this, but Ferris Bueller Changed His Mind”

Start your email copy with a line about how this is the biggest discount your brand has ever ran on sweaters and you will never run one like this again. Tell a short story about how your CEO strongly advised against this, but your marketing team ran with it anyways. Now a parade has broken out downtown and everyone is dancing to Twist and Shout in their new sweaters.

Make things interesting. Be different. Stand out.

First, I was curious. Then I was genuinely interested. Now you’ve made my day and I’m about to buy a sweater after I pull up Ferris Bueller’s parade scene in another tab.P

How Engine Mail Can Help

Engine Mail was built by e-commerce veterans based on their past experiences in online retail. The aim is to provide an email automation product that is superior to anything you’ll find elsewhere. That includes the best possible tools for delivering high-quality email subject lines. 

Our primary goal throughout that process has been ease of use. We understand we’re competing in a landscape full of complex, confusing, and overdone email products. We’ve made sure Engine Mail isn’t falling into that category. The Engine team has taken what they know best throughout years of navigating the world of e-commerce and manufactured a product around email automation that is easy to understand and use.

We’re aware your most precious asset is time, so we won’t take more than 15 minutes of your time to create exceptional email flows for you. Set up a call with us by clicking here or reaching out via email. Your business will thank you later.