How to Come Up With Effective Email Subject Lines for Your Marketing Emails (+ Examples)
Alejandra Zilak | May 5, 2017 | 12 min read
1. Why Email Subject Lines Are Crucial
2. Email Subject Lines Statistics
3. What Makes an Effective Email Subject Line?
4. How To Craft the Perfect Email Subject Lines
5. Email Subject Line Best Practices
6. Types of Subject Lines + Examples
Once upon a time, in the days of America Online and dial-up internet, it was exciting to receive email notifications. We got that same dopamine hit we get when we receive a social media or delivery notification of a long-awaited package.
Nowadays, however, email is everywhere. You need to create accounts to pay your bills online. You give it to business websites to get a discount code for your first purchase. You likely have multiple inboxes — a personal one, a work one, and one where you attempt to keep all junk and other unwanted messages.
It's an avalanche. We delete most of them without reading them. We install spam filters to avoid receiving a lot more. Yet, it's still an effective form of marketing. In fact, generally, it yields a 4,200% percent ROI.
But for it to work, you gotta make sure people are actually reading them. Therefore, it's essential to stand out in this expansive sea of messages. And doing so takes a lot of strategizing, trial and error.
Why Email Subject Lines Are Crucial
The most obvious reason why email subject lines are critical is that if nobody opens your marketing emails, it doesn't even matter how good the content is. In theory, this makes a lot of sense. In practice, there are additional reasons why they matter so much:
You only have a few seconds to get readers' attention. Smart phones and instant gratification have created a culture of short attention spans. Three seconds, to be exact.
You have very limited space. Anything longer than 60 characters will be cut off in the subject line window; and unless you're a master at creating suspense, that will likely result in readers deleting them without opening.
Readers may be reading from tiny screens. Most people check their emails from their phones or tablets. So when you craft email subject lines, you have to design them with these limitations in mind.
Email Subject Lines Statistics
Something else you want to keep in mind are the numbers. You may have previous experience with email marketing, or maybe you've read about other small business owners' experiences on online forums or heard about them at networking events. But let's take a closer look at statistics:
By the end of 2022, there will be approximately 4.2 billion email users worldwide.
35% of email recipients decide whether to open a marketing email based on the subject line.
54% of small businesses use email marketing to communicate with their customers.
81% of small and medium sized businesses (SMBs) rely on marketing emails to acquire new customers; while 80% use it to retain existing ones.
59% of B2B marketers say marketing emails are their most effective way to generate revenue.
Consumers who make purchases when clicking through a website from a marketing email spend on average 138% more than web visitors from other sources.
These numbers speak for themselves. Email marketing is convenient, reaches an audience on their own terms (when they have time to pay attention to you), and it's effective. Knowing this, it's even more imperative to get those subject lines right.
What Makes an Effective Email Subject Line?
An effective email subject line is one that piques the interest of your buyer persona. Different audiences have different requirements, so taking into account factors such as their demographics, education level, job roles, and pain points, will help you figure out how to craft your content.
In addition, you want to take into account their stage on their buyer's journey. A first-time website visitor who just gave you their email address today should not be receiving the same marketing emails as a repeat customer. And these considerations should be reflected in your email subject lines. However, these are just starting points, and require additional considerations, as described below.
How To Craft the Perfect Email Subject Lines
Although email subject lines are short, they require a significant amount of time. The shorter the content, the harder it is to write it. While it's not possible to implement every single one of these best practices in every subject line, try to use them all throughout your campaigns.
Consider a Free Offer
Who doesn't want free stuff? A go-to way to entice subscribers is to have an email subject line with a free offer. It can be a physical product like a sample or it can be a content offer like a whitepaper or ebook. According to Sidekick, subscribers were 10 percent more likely to open emails that had a subject line with the word Free.
Personalize the Email
Address your customers by their name for a personal touch. Not only does this help build relationships with customers, it also differentiates yourself from the competition when they use generic greetings for emails. To easily customize your email to each customer, use a platform for email marketing that uses personalization tokens to insert first names automatically in subject lines.
Use FOMO
Fear of missing out isn't just something people try to instill through social media posts. It also works well as a way to promote an event or product. Let your audience know that you are currently offering an extraordinary opportunity that they will miss if they don't open your email. This can include messages such as You're Missing Out On ____, One Day Only, or Ready for _______?
Instill Curiosity
Tease them with a phrase about what they will find out if they open your email. This could be tips and tricks that will alleviate a pain point you know they're experiencing, announcing the winner of a contest, or telling them that you've been waiting a while to finally tell them XYZ.
Use a Compelling Call to Action
Like landing pages, emails thrive on calls to action to encourage customers to move forward in a sales funnel and eventually make that purchasing decision.
Examples of compelling calls to action for email subject lines include:
These examples suggest the action to take and at the same time tell subscribers how they will likely benefit from opening the email, such as claiming a free offer.
Provide a Sense of Urgency
The Email Institute found subject lines that have a sense of urgency and exclusivity are opened 22 percent more than ones that did not. Words like "Now," "Quick" and "Limited Time" help give the idea that it is currently the right time to buy. Phrases like "Exclusive Offer" or "Members Only" let customers know that these offers are also good for a certain amount of time, but also allows them to feel like they are special and valued.
Optimize for Mobile
With the increased use of mobile devices, marketers have had to adapt their email subject lines to suit subscribers on the go. Consumers who read emails on their mobile phones or tablets tend to scan their inbox and they may be turned off by long subject lines. Instead, use subjects that are short and use simple words.
According to Boomerang, subject lines that use between three to four words are opened the most. In addition, lines that had words that were four letters or fewer had a higher open rate.
Overall, optimizing for mobile is a huge trend in inbound marketing — especially since most people check their emails from their phones. And those who do immediately delete emails that don't load correctly on their mobile devices.
Conduct A/B Testing
It's easy to be disappointed when subscribers do not open emails. It feels even worse when marketers are sure they used catchy subject lines. Take the guesswork out of whether your recipients would prefer a subject line over other iterations by testing them and analyzing the outcomes.
Inbound marketers often use A/B testing to determine whether subscribers are more likely to click on one subject line over another, collecting hard data to support the effectiveness of an email heading. They can use testing and analytics to gather information on key performance metrics — such as open rates and clickthrough rates. This information allows you to modify your marketing strategy and improve email subject lines and design.
Lead With a Question
Asking questions in subject lines is another way to actively engage with customers before they open marketing messages. In a study conducted by Mailchimp, results found that subject lines that include questions perform better than those that don't.
Questions are also great to get customers to think about pain points that can be solved with a brand's products or services.
Email Subject Lines Best Practices
Limit it to 60 Characters
This is mentioned above, but it bears repeating: Don't risk getting your subject lines truncated. That small amount of space is prime real estate, and limiting it to 60 characters ensures that your readers are able to see the entire subject line.
Tell What's Inside
While piquing interest is a great way to get people to open your email, you don't want to play a guessing game. Everyone's busy. Let them know at least what the topic is about and what they'll find out when they open it.
Make It Timely
If you want your emails to resonate with your target audience, you have to make them relevant to what they're living. It could be the holidays, ______, or hey, a worldwide pandemic! Use whichever circumstances they're living through as long as it's related to your email content.
Use Action-Oriented Words
Action words motivate people to (drum roll, please) take a desired action. It's not the same thing to say "We are hosting a webinar" than "Enroll in our free webinar". One is passive. Informational, but flat. The other one invites the reader to actually do something about it.
Don't Use All Caps
Ay, ay, ay. Do we really have to tell you two decades into the millennium that all caps is the equivalent of yelling? It does. So don't do it.
Mind the Preview Text
While the preview text is outside the subject line, it still gives readers a glimpse of what's inside your marketing emails before they open them. Use this to your advantage by expanding on the subject line and limit it to 40 characters.
Be Mindful of Tone
If you have a business, hopefully you also have an established brand voice. This could be humorous, irreverent, or scholarly. Something that helps your readers immediately recognize that the message is coming from you.
Use Numbers
People like lists. They're scannable and straight to the point. Got five tips to help your buyer persona do whatever it is they want to do? Include it in the subject line. 5 Ways to Increase Sales. 3 Tips to Grow Your Business. 7 Lasagna Recipes To Make Your Grandma Proud.
Including someone's name and/or a subject line that's specifically relevant to the recipient will get their attention. This can include their geographical location, their preferences or affinities to a particular thing, or anything relating to recent activity they've engaged in on your website.
Consider Using Emojis
Granted, this one depends on your type of business. Don't try to be cute if you're a divorce attorney or run a funeral home. But if you're in a creative industry or something equally fun or refreshing, emojis can help add personality. Used sparingly, they can help you increase your email open rate.
Avoid Looking Spammy
This one's a double whammy: You'll annoy people and you increase the likelihood of being sent automatically to their spam folder by their email service provider. To prevent this from happening, avoid using words that sound too promotional, such as As Seen on TV! Anything with the word cash on it, dollar signs, or anything else that makes your emails look like you're trying to get someone to join a pyramid scheme.
Types of Subject Lines + Examples
Alright, so let's look at some marketing email subject lines in action.
Personalized Email Subject Line
Emails that are very specific to the reader will substantially increase the likelihood that they will open it. This is especially the case when the subject line makes reference to an action previously taken by the customer:
Promotional Email Subject Line
1-800 contacts now lets customers renew their prescriptions directly from their app. All you have to do is set your phone at an instructed distance from your eyes and answer questions asked by the application. All of this doesn't fit into an email subject line, but telling you that you can do it in 10 minutes does:
Follow Up Email Subject Line
As if it weren't convenient enough that electronics now save credit card information for faster checkouts from your couch, Under Armour enables your shopaholic tendencies by letting you know when an item you wanted to buy a few weeks ago is back in stock:
Abandoned Cart Email Subject Line
Abandoned cart emails are also a way to personalize your messages, since they are relevant only to that specific reader. And since all of these examples are straight out of my own inbox, look at yet another one from Under Armour (Bonus: Look at how they leveraged the extra space in the preview text):
Last Chance Email Subject Lines
Listen, that sale ends TODAY. Why would you want to pay more later? Open this email now and get that item you've been pining after for a while.
As you can see, drafting email subject lines is time-consuming and requires a lot of considerations. But they're definitely one of the most important parts of your email marketing campaigns. And having a platform with features like segmentation and automation will make this process a lot easier for you.
Alejandra Zilak
Alejandra Zilak is a content writer, ghostwriter, blogger, and editor. She has a bachelor's degree in journalism and a Juris Doctor. She's licensed to practice law in four jurisdictions and worked as an attorney for almost a decade before switching careers to write full time. She loves being part of the Bluleadz team and implementing SEO best practices with her content. When not working, she loves to read, write fiction, and long distance running.