Email Subject Line Best Practices to Make You a Marketing Ninja!

The email subject line is the first thing that your subscribers or customers see when they receive an email in their inbox. This single line is enough to determine whether your email is opened, marked as spam, or sent right to the bin.

Most marketers, like you, might be divided on the importance of email subject lines. But, stay with me.

When was the last time you opened an email without looking at the subject line?

Be it from a friend or from a brand that you love or even from your office – you decide the urgency of opening an email based purely on the content in the email subject.

You might think that crafting an email subject line is easy. Right? And, if you think four catchy words is all it takes then you’re wrong!

Did you know that between 2014 and 2018 an average person received about 90 emails a day and about 40 business emails were sent every day. As a data-driven marketer, you rate a successful campaign on the basis of open rates and click-through rates your emails receive.

In order to hit higher email open rates, your subject lines have to be good enough to grab attention as soon as they land in your customers’ inbox. Good subject lines are often personal, descriptive, humorous while giving recipients a strong reason to open your emails.

Email Benchmark Report
Source: MarketingSherpa

We’ve analysed millions of emails sent by our clients through Smartech to find what practices result in the best email open rates and click-through rates. We’ve compiled some of the best email subject line practices for you!

Follow these and you’ll definitely see an uplift in your user engagement rates. The more you learn about subject lines the better you’re likely to understand your subscribers and their preferences.  

Segment your Email Subscription List

Email marketing has proven to be one of the most effective marketing channels over a period of time. One major reason for its success is because of email subscriber segmentation.

You might be sending the same email campaign to your entire target audience as a broadcast. While this email might be helpful and informative to some it might not be relevant to the rest of your target audience.

You need to segment your email subscribers based on varied parameters such as:

  1. Geography
  2. Age
  3. Gender
  4. Time
  5. Activity
  6. Industry
  7. Stage of sales cycle
  8. Free user
  9. Paid user
  10. Previous purchase history

Email List Segmentation Results
Source: Source: Lyris, Inc.

Every user is different and they have their own likes and interests. They come with varied experiences and have a unique experience with your product/brand.

Through effective user segmentation you’ll be able to send hyper-personalised and targeted subject lines that are tailored according to specific user segments. By doing this you’ll not only see a great uplift in your email campaign results but also generate intent-based leads that are more likely to convert.

Communicate a Sense of Urgency and Scarcity

Have you ever purchased an expensive online course only because there were very few seats remaining?  It’s not just you! As humans, we are more likely to respond and act quickly when we sense urgency and scarcity.

And, it is this facet of human psychology that you could leverage while crafting high-conversion email subject lines.

Subject lines that instill urgency and excitement are more likely to inspire your subscribers to open your email. Think of your subject lines as subtle calls-to-action that gently compel subscribers to see what your email campaign is all about.

Email Subject Line Power Words

Keep it Short and Simple (K.I.S.S)

Always remember that your subscribers receive a ton of emails every day. Their inbox gets flooded with all kinds of emails, right from personal to work and promotional. It is easy for your email to get lost in this chaos and never be found and opened.

One way to break through the clutter is to keep your email subject lines short and simple. Yes, it can be challenging to write something really short that can convey the entire message of the email. But, that/s the power of brevity aligned with your goal is to get noticed and increase open rates.   

For instance, if you’re sending the status for an order, “Your order is on the way”, reads way better than “Your order #IDP11330443 will be delivered shortly”.

In fact, Brian Dean, Founder of Backlinko, has mentioned that email subject lines that don’t exceed 16 characters have significantly higher open rates. He attributes this to two key factors:

  1. Emails with shorter subject lines are likely to be delivered more frequently
  2. Shorter subject lines tend to create more curiosity

Title Case your Subject Lines

Email subject lines are often written in four cases:

  1. Title Case – “The First Letter Of Each Word In The Subject Line Starts With Upper Case”Note: You can also opt to use lowercase with regards to the articles, conjunctions, and prepositions three letters long or fewer, except for the first word. Eg: “The First Letter of Each Word in the Subject Line Starts with Upper Case”
  2. Sentence Case – “The first letter of the first word in the subject line starts with upper case”
  3. Lower Case – “all the letters in the subject line are lower case”
  4. Upper Case – “ALL THE LETTERS IN THE SUBJECT LINE ARE UPPER CASE”

According to ConversionXL, writing your subject lines in title case potentially increases your open rates. In addition to that, Yesware, a leading sales productivity platform, has also affirmed the use of title case in email subject lines after analysing thousands of email subject lines.

Email Subject Line TItle Case

To summarise –

Best Subject Lines: Title Case

Good Subject Lines: Sentence Case

Ok Subject Lines: Lower Case

Play Safe with Punctuations

Using punctuations in a sentence adds meaning to it. So does using them in email subject lines. But certain punctuations might not be received positively or as intended by the recipient.

One common mistake that most marketers make is using a question mark (?) and an exclamation mark (!) in the same sentence. Did you know the PLING QUERY Rule is a directive by the Apache web server that flags emails as spam if your email subject line contains both “?” and “!”.

This is precisely why you need to use punctuations only when necessary.

Personalise your Subject Lines

Personalisation is critical to elevating your email open and click rates. It not only helps in getting your subject line noticed, but also results in higher user engagement. In fact, personalised email subject lines can boost your open rates by 50%.

Always remember, no two subscribers are exactly the same, which means your email subject lines can’t afford to be the same. You can personalise your subject lines through the following:

  1. Use Recipients First Name or Location:When was the last time you opened an email which was addressed to you as a user or customer? Personalising your email subject lines with either the recipient’s first name or location can be highly effective. It also makes your recipient curious to check out your email content resulting in increasing open rates.

    Email Subject Line Personalisation

  2. Use Emojis:Marketers have started to tap into the potential of emojis. Emojis have gained a lot of traction in both personal and professional communication in recent years. Including them in your email subject lines will definitely add greater personality and colour to your email campaign, right from the first glance. In fact, when leveraged correctly, emojis can boost your open rates by almost 56%! For instance:

    Email Subject Line Emojis

  3. Ask Contextual and Relevant Questions:Asking questions in your subject lines is a clever way to nudge your subscribers into opening the email. Especially when you know your question is contextual and relevant to your subscribers. This helps pique your subscribers’ interest while capturing their behaviour to the question.For instance, “Are you using these subject lines?” is a better subject line to use when compared to “Best email subject lines”.

Don’t Mislead your Subscribers

Always tell your subscribers what’s inside your email, or at least create enough curiosity around the same.

For instance, if your business revolves around content marketing, then you might have set your email drip campaigns for those who have subscribed to your blog and for those who have downloaded a content asset. While most emails reach your users in real-time there are cases where they don’t receive it. In such cases you’d not want your users to get surprised and act aloof with your complex subject lines. It is always better to let your users know what’s inside the email.

Using “Your new e-book inside” or “Your invoice is ready!” always better than “Thank you for downloading” or “Thank you for shopping”!

Use a Subject Line Tester

While, you may have created an effective subject line, there will always be scope for improvement. And to help you there are tools that can help you analyse and better your email subject line. Coschedule’s free email subject line tester will be ultra-handy to marketers like you and help you get more clicks, opens and ultimately conversions. Using an email subject line tester will help you derive a more data-driven approach to drive higher open rates. You can also check your email campaign’s title performance using our campaign title performance predictor. It uses AI to predict the campaign performance and also suggests titles that’ll drive higher conversions and CTRs.

A/B Test your Subject Lines

While these best practices will prop you up for potential email marketing success, you need to realise that what’s worked for others might not always work for you. In order to uplift your campaign performance, you need to understand how different segments of your target audience react to your subject lines.

This is where A/B testing your email subject line helps. You might be mostly using your intuition to predict and decide on what subject lines will nudge subscribers to click on your emails. But, instead of your intuition you should always A/B test your subject lines, and based on data, tweak the wording accordingly to improve your results.

By A/B testing you’ll be able to determine:

  1. What works best for your audience: Long or short subject lines?
  2. Numbers or no numbers?
  3. Statements or questions?
  4. Fewer emojis or more?

Hyper-personalising your email subject lines based on the customer’s historical data on open and click rates will help in increasing conversion rates. Using our AI-powered subject line optimiser, you can determine the best possible subject line for a campaign.

Parting Thoughts

There’s no one rule fits all. Whatever your strategy or approach is, it is important to keep your target audience in mind and always experiment with your subject lines based on the right keywords and phrases to identify what they resonate well with.

The goal of creating a perfect email subject line is like a moving target. What worked yesterday is unlikely to work today. You must constantly stay up-to-date on spam triggers and remain in touch with your subscribers’ evolving needs, behaviours, and interests.

To find out just how you can optimise your email campaign performance to hit incredible marketing ROIs, get in touch, today!

Vijay Mandeep

Vijay Mandeep

Vijay Mandeep is a data-driven B2B Saas marketer with a vested interest in startups. He’s passionate about growth hacking, content marketing, and everything social media for B2B SaaS. He works as Senior Growth Marketer at Smartech.