How to Write Great Subject Lines That Get Your Emails Opened

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Email marketing can be used to build and maintain a strong relationship with your customers. And a great subject line can make or break your email marketing strategy. So let’s take a look at the key ingredients that make an irresistible subject line.

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Email subject line terms

Before we dive into the practical stuff, here are some useful terms to help you understand the concept of emails and email subject lines a little better.

  • Email subject line.
    The line of text that briefly explains the email topic in the recipient’s inbox. Humour, wordplay and offers are often used to inspire people to open and read on.

  • Email body.
    The main part of the email containing your message content.

  • Email marketing.
    The method of sending a message to customers via email. There’s nothing to say that an email sent to one individual can’t be considered email marketing as much as an email to a group of people would be.

  • Targeted email.
    An email that has been written and designed for a specific type of customer in mind.

  • E-blast.
    An email sent out to many recipients. E-blasts are often considered spam when they don’t use any kind of targeting.

  • Open rate.
    The percentage of delivered emails that get opened by recipients.

  • Bounce rate.
    The percentage of recipients that don’t receive your email, often because their email is no longer in use.

  • Mailing list.
    A list of email addresses, usually accompanied with the recipient’s name and other personal information, used by businesses to send emails to multiple recipients.

  • Opt-in.
    Where an individual actively chooses to be added to an email list.

Why are email subject lines so important?

According to marketing specialists Sign-Up.to, the average open rate for opted-in emails is 25.44% in the UK. That might not sound like a lot, but when you consider that people receive an average of 42 emails every day, it’s no wonder. Customers are bombarded with messages — yours has to be worth their time. A good subject line cuts through the noise of hundreds, sometimes thousands of emails to get your audience’s attention. A great subject line gets them curious, convincing them to open that email and see what’s inside.

Imagine going to an industry networking event. One of the things you spend time preparing is your personal introduction — you know you have to make an impression fast, and email subject lines are similar.

Tips for writing great subject lines

Something you’ll begin to learn as a business owner wearing a marketer’s hat, is that marketing is as much about testing as it is laying down a strategy or having great ideas. The tips below are just a handful of ways to improve the way you write email subject lines, but your customers are unique — the more you experiment and test, the closer you’ll get to finding the sweet spot.

  • Target specific customer segments.
    Rather than writing generic subject lines, segment your mailing list according to what you know about your contacts, e.g. their age, where they live, how loyal a customer they are. These all affect the messages you target them with.

  • Know your character limits.
    Subject lines that don’t fit within the space provided in recipients’ inboxes get truncated, cutting off part of the text you’ve spent time writing. This risks your message not being read in full, and it doesn’t look great either. Get to know the different subject line character limits for different browsers (e.g. Google Chrome and Firefox) and devices (e.g. the iPhone X or Samsung Galaxy S8).

  • Include recipients’ names.
    If you’ve collected people’s names along with their email addresses, you can automatically include them in email subject lines. According to Hubspot, this increases open rates.

  • Don’t overdo it.
    Humour, urgency, storytelling and emojis are powerful tools to improve what would otherwise be a generic subject line. But if you ever find yourself doing the same thing again and again, pull back a bit. Overusing these techniques and tools can come across as contrived. You end up desensitising your mailing list, and even annoying them.

  • Keep it succinct.
    The fewer words you can use to make your point, the better. Long subject lines take longer to read, increasing the risk of the recipient getting distracted before they fully digest your message.

  • Don’t be misleading.
    A definite no-no in email marketing is drawing someone in with a subject line that has nothing to do with what’s inside in the email body. It reflects poorly on your attitude towards your customers and general brand philosophy

How do I measure success?

Measuring success always starts with understanding exactly what “success” is, which loops in with your overall business strategy. Open rate is the standard metric used when testing email subject lines, but you can also measure the click-through rate (how many people click on a link in the email body), conversion rate (how many people click-through from an email to then spend money with you) and even unsubscribe rate (how many people are leaving your mailing list).

There are many email marketing platforms that will help you send, track and measure the performance of your emails, including:

This article is intended to offer helpful guidance and does not constitute qualified legal advice. Please consult an independent legal advisor, if you have any marketing questions pertaining to your particular business.

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