Email marketing is a great way to nurture leads and continue to develop relationships with customers. Yet, executing an effective email marketing strategy can be tricky. Formatting the layout, choosing the right contact list, and having quality calls to action are just a few pieces of the puzzle when it comes to building an effective email campaign. However, none of the above elements will ever even be seen by your audience if they don't open the email to begin with. How do you ensure they will? A killer subject line.

According to Super Office, in 2020, the average B2B email open-rate was 21.3%. So what causes people to decide whether or not they want to open an email? One of the most important deciding factors is the subject line. The subject line is one of the first pieces of an email that a recipient will see. Ultimately, it’s imperative that email marketers create subject lines that motivate the recipient to open the email.

In this article, we’re discussing best practices for writing subject lines so good your contacts will be eager to see what's inside!

Why are Subject Lines Important?

Subject lines are like first impressions. You only have one chance to do it right. Essentially, the subject line is one of the main reasons why a person chooses to open your email or toss it in the trash. If the subject line lacks relevance to a customer, odds are they won’t open it. Actually, in 2018, the average delete-before-reading rate reached 16% and that number is expected to continue growing. Moreover, if a subject line is boring or uninteresting, there’s an even greater chance that not only will the customer disregard the email, but the email won’t stand out and will probably just get lost in their inbox.

Think of subject lines like a relationship, you want to make a positive first impression. But you also need to keep the “romance and fun” alive to keep the relationship on an upward trajectory. By continuously providing impactful subject lines, the reader will stay engaged and continue to open emails throughout your campaign.

Best Practices for Writing Subject Lines

The best subject lines accurately communicate the value of the content inside the email. In 60 characters or less email marketers need to adequately describe what the reader will gain from opening and reading the email. Sounds tough, right? Creating perfect subject lines doesn’t happen overnight. Yet sometimes, all it takes is a little practice and trial-and-error to see which types of subject lines your contacts are responding to. We’ve compiled a list of best practices for writing subject lines to make the process easier for you.

Keep it Short and Simple

Write your subject line in 60 characters or less. These days, most people are checking their inbox via mobile devices. These small screens don’t allow for a lot of text to show for each email that's received. You don’t want to have your subject line cut off prematurely — it might cost you an open! Additionally, limit the use of all caps and special characters and symbols. These tend to trigger spam filters.

Add Personalization

People are 26% more likely to open emails with personalized subject lines. But what does personalization entail? Personalizing an email can include the reader’s name, job title, recent purchase information, or any other information you may have collected through your contact database. Most email marketing software will provide personalization tags to simply add in any segment of a contact’s information to the subject line.

Carefully Use Emojis

Emojis can be attention-grabbing, but including too many of them too often can send your email directly to spam. Also, you want to be on the lookout for how an emoji is displayed on various devices and email providers like Gmail and Yahoo. Be sure to test how the emojis appear in multiple scenarios before hitting send.

Ask a Question

As humans, we’re naturally curious. Questions in subject lines are likely to achieve engagement as they pique a reader’s interest. Mostly, questions inspire readers to open the email in search of the answer.

For example, the subject line, “Zillow: ‘What Can You Afford?’” captures a reader’s interest. If someone is receiving emails from Zillow, odds are they are interested in buying or renting a house or apartment. They’re likely to not only want to but need to know what type of living situation they can afford. Wanting to find out the answer, the reader will be more likely to open the email.

Don’t Write Clickbait Subject Lines

Have you ever opened an article on social media whose title was something like, "How to use analytics to improve your sales win rates" but the article you’re taken to is about only the analytics the particular software provider has in their feature set. This is the epitome of clickbait — and we fall for it every time.

While clickbait subject lines may initially capture your audience's attention, if the content in the email doesn’t reflect what the subject line promised, customers will grow to distrust your brand. 67% of consumers say that once a brand loses their trust, the trust can never be gained back. Bottom line – ensure your subject lines are genuine and relevant to the content inside the email. By being straightforward in the subject line and following through within the email body, you can deliver on your promise and connect with an interested audience from the get-go.

Pro tip: Read every subject line out loud to yourself. Would you want to open this email? Would your buyer personas open it?

Subject Line Faux Pas that Will Send You Right to Spam

Ah, the spam folder. It’s basically the equivalent of purgatory for emails. This is the last place marketers want their emails to end up (and the last place a customer will go to look for an email from your business). Luckily, there are a few actions you can take to ensure your emails slide straight into the inbox without getting caught up in spam filters. Primarily, the subject line is one of the most relevant triggers for spam filters.

Phrases like “#1” and “100% FREE” in subject lines are considered trigger words. Trigger words alert an email provider’s spam filter and snatch up that email before it can hit the inbox. If your emails are getting caught in spam filters, try to avoid using trigger words and phases in your emails.

Besides trigger words, using all caps and certain symbols like the dollar sign in your subject line can send your emails into the spam folder. The harsh reality is that often the emails with subject lines including a lot of symbols, exclamation points, or phrases like “Cashcashcash” tend to be actual spam. Ultimately, a brand that is associated with spam is a brand that lacks credibility and loses trust with their target audience.

A/B Test Subject Lines

MailChimp defines A/B testing as the process of testing “different versions of a single email to see how small changes can have an impact on your results.” Sometimes, in order to give the people what they want, we need to ask them what they want first. A/B testing subject lines is a great way to figure out which types of phrases, words, and tones your target audience respond best to in regards to email subject lines.

You can have a great subject line but it may only work for a specific buyer persona. To understand how particular audiences engage, try different phrasing or sales offers to see what gets the most attention. Once you have your results, modify the wording to reflect the subject line that performed better. The results should also be able to tell you what types of phrases work best for your audience: long or short, questions or statements, serious or funny.

A/B testing is good practice for continuously improving your email marketing over time. Customers’ wants and needs change year after year. A/B testing enables you to keep up to date with your customers’ growing expectations.

The 7 Types of Successful Subject Lines

HubSpot recently stated that there are 7 types of successful subject lines and we’re highlighting them all here for your reference.

1. Fear of Missing Out Subject Lines

People hate missing out on good deals, good times, and great opportunities. These subject lines cause people to react out of worry that they have limited time to reap the benefits of the content inside the email, i.e. a 24-hour sale.

Killington Ski Resort: “Season Pass Savings Disappear Thursday”

This subject line informs the reader that time is running out for a huge discount on season passes. If they don’t take action by Thursday, they’d have to pay full price for a pass when just a day ago the pass was 30% off.

2. Curious Subject Lines

The human brain is naturally curious. We want to know the interesting facts that the internet holds. Don’t you? Take a look at the example below from LinkedIn.

LinkedIn: “This is how much working from home saves you”

Wouldn’t you like to know just how much money working from home can save you? Curious subject lines capture a reader’s attention and leave them wanting more. This curiosity is what prompts the reader to then open the email and discover the answer.

3. Funny Subject Lines

Funny subject lines are eye-catching and stand out from the hundreds of ordinary emails in an inbox. Keep in mind, what people find funny may differ depending on the audience. It’s best to know your buyer personas to have a greater understanding of what a set of contacts would find humorous.

Red Sox Ticketing: “Come to Fenway May 2 - we won’t tell your boss!”

This subject line works because the email marketer knows their target audience: people who love baseball and would be interested in attending opening day (regardless of their work schedule). The subject line informs the reader about an upcoming baseball game that’s relevant to them while adding a fun flare piquing their interest. You could say the Red Sox “hit it out of the park” with this subject line!

4. Address Pain Points

People among all industries want to feel as if their problems are being seen and addressed. Subject lines that address pain points increase email open rates from relevant customers.

Adobe Stock: “Beautiful brochures made faster”

It’s safe to assume that this subject line could be connected to an email that was sent to small business owners. Many small business owners do a majority of their own marketing. But the problem is they’re not marketers or graphic designers and they don’t know how to create effective brochures. Adobe is offering a solution to this problem by helping them create marketing materials quickly!

5. Reengagement Subject Lines

Sometimes, even the most loyal customers disengage due to changes in their personal life or some outside reason. Reengagement subject lines help put your brand at the forefront of their inbox again. Think about this scenario, you’re a marketer at Marriott and a loyal customer hasn’t stayed at a hotel of yours in quite some time. Below is an actual subject line Marriott has used to re-engage with its customers:

Marriott Rewards: “We’ve missed you, [Name]! Please come back!”

This subject line also adds a personalization tag to grab the attention of the reader. It may also be a good idea to include a special offer to entice the reader to book another stay.

6. Emoji Subject Lines

As stated previously, emojis can be extremely effective at capturing your target audience’s attention. However, they need to be used in moderation so as not to trigger spam filters. Take a look at the example below.

ClassPass: “Go from 🌱 to 🌳 for just $4”

With very few words, this subject line tells a story. The reader knows everything they need to with two emojis. Essentially, the meaning of this subject line is that in choosing to use ClassPass, clients can grow strong with just $4.

7. Social Proof Subject Lines

Social proof subject lines are based on the idea that people will adapt their behavior according to what other people are doing. Take a look at the subject line below, for example.

Inc: “18 Habits Highly Successful People Have (And the Rest of Us Probably Don’t)”

This subject line basically states that successful people have something the reader doesn’t. If that email held all the secrets to how to become successful like a role model of yours, wouldn’t you want to open it?