8 Tips to Write Email Subject Lines That Will Get Opened

8 Tips to Write Email Subject Lines That Will Get Opened

According to experts, not including a subject line in your email marketing campaign is one of the biggest mistakes you can make. It not only determines whether your email is opened but also how the recipient responds. After all, in the digital world, where most of us receive hundreds of emails a week, would you open an email with a blank subject line? Chances are, that email would either end up being deleted or lost in the recipient's spam folder.

What is an email subject line?

The subject line of an email is the first thing a recipient sees when an email reaches their inbox. Just like the heading of an article or the opening line of a book, it determines whether it sparks the interest of the reader or is discarded. Ensuring your email subject line is optimised towards your audience is therefore of vital importance.

What do you put in the subject line of an email?

The purpose of a subject line is to communicate exactly what your email is about. This allows recipients to prioritise the email's importance without even having to open it. While the general rule of thumb is to keep them informative, catchy, and brief, what you include in your subject line will be largely dependent on the context of your email. To help you get started, here are a few of our top tips to writing email subject lines that will get opened. 

How do you write an email subject line that gets opened? 

1) Personalise your email subject line

Did you know that emails with personalised subject lines are 26 percent more likely to be opened? Historically, personalisation in email subject lines meant including the recipient's name, but now this term covers a whole range of components. The most successful personalisation strategies generally involve: segmentation (targeting customers based on their demographics and purchase history, etc.); dynamic content (content adapted to customers' precise interests); and email automation (sending relevant emails to customers at the time they are most likely to open them).

Example: Get a personalized highlight reel of your hosting success

2) Keep it short

The latest stats tell us that 47 percent of all people across demographics use a mobile device for checking their email. This echoes the importance of making emails optimised for smartphones — and that includes subject lines. To avoid getting cut off on mobile inboxes, aim to keep your subject line to under 40 characters long (or about five to seven words long). As we mentioned previously, you should also bear in mind that the majority of users won't read an email if it doesn't automatically grab their attention first. If you're mentioning several things in your subject line, you should therefore include the most important part before anything else.

Example: Take control of your banking

3) Avoid spam words

Subject lines that use aggressive or salesy language will most likely land your email in your recipient's junk folder since they automatically trigger spam filters from many inbox providers. To avoid this outcome, where possible, avoid using loud punctuation like all caps or multiple exclamation marks, as well as overtly promotional language like “buy now or “free. As an alternative, demonstrate your expertise in a subject area by sharing information your audience will find useful. 

Example: 20% off accessories this festive period

4) Ask open-ended questions 

What better way to pique readers' curiosity than to ask questions in your subject lines? Catch your reader's attention with a good one and you'll most likely inspire them to open your email in search of the answer. Rather than starting a sentence and finishing it in the email body (which could be seen as clickbait) ask an open-ended question which you can expand on throughout the rest of the content, or perhaps by linking to a featured blog post in a particular section of your campaign.

Example: What inspires you?

5) Use logical keywords for search and filtering

Keyword research doesn't just tell you what your audience is searching for — it tells you what topics they're most interested in. Using frequently searched keywords in your email subject lines and copy will therefore increase your chances of achieving higher open rates since the more interested someone is in a topic, the more likely they are to notice and open an email about it. It's also worth bearing in mind that many professionals have filters and folders set up to manage their email so it's important to include keywords related to the topic of the email that will make it searchable later.

Example: 5 city guides for your next long weekend away

6. Include a deadline in the subject line

With so many emails flooding our inboxes and plenty of distractions elsewhere, it's no wonder that so many emails remain unopened by recipients. To encourage readers to prioritise your email, create a sense of urgency by including a deadline in the subject line. If, for example, you have a special event or limited-time discount, you can attract readers' attention by sending a series of emails. You could start with an initial announcement, letting your customers know about an upcoming date, and then as the deadline approaches, remind them of the promotion in a ‘last chance' follow-up email. 

Example: Long season, short sale.

7. Spark interest with a teaser 

Another way to gain the interest of readers is by giving them a preview of something exclusive you're offering. The best movie trailers get the audience excited for the release date by explaining the premise behind the movie without giving away the good parts. A great subject line should do the same thing. Build anticipation amongst customers by creating email teaser campaigns for everything from upcoming sales and new product launches to special events. 

Example: Something new is coming to Havenly...

8. Make an announcement

Got something new and exciting to share about your business or organisation? Readers respond to enthusiasm, so be sure you channel exactly that in your subject line when making an announcement. Sharing announcements on your email channel before anywhere else also creates a sense of exclusivity, thereby encouraging recipients to open the email quickly. Remember that readers have already showed some interest by signing up to your subscriber list in the first place — so unlike with other forms of marketing, you're already halfway there with email.

Example: 2-for-1 Packs are Back!

Register today for our Mailchimp Intro course where you'll learn how to create and send professional email campaigns, gain a deeper insight into reporting, and analyse data to improve conversions.

by Emma Gibbins | 27 Sep 23

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