Advice on how to write the perfect email marketing subject line for your clients

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It doesn’t matter how insightful, engaging or useful you make the content of your marketing emails and newsletters if people don’t open them.

And assuming your recipients signed-up to receive your emails, there’s only thing standing between an open and a delete – and that’s the subject line.

Anyone that’s spent any time at all working in email marketing will know how important that subject line is – and how tortuous the process of writing one can be.

Do you hint at the goodies inside, or spill the beans upfront? Do you ask a question or make a statement? Should you be playful, serious, offbeat, intriguing or factual?

Of course, there is no correct answer – different approaches work for different organisations, depending on the purpose of your communication, your brand’s tone of voice, and your audience’s expectations.

But knowing there’s a million and one ways you could go about writing that subject line doesn’t help when you’re up against a deadline and you need some inspiration fast. So here’s a little help next time you see the blinking cursor and want to test something new (and we strongly encourage you to test, including A/B tests to see what works best).

First, take a look at this post – it’s a list of 540 email subject lines from “successful marketers.” These are quite US focussed a little too salesy for our liking – but interesting themes emerge:

“how to” appeared 49 times in this list

“your” appeared 90 times

“you” appeared 83 times

36 emails had ellipses in them – … or . . .

Gary V used emoticons in some of his subject lines

Many included a lot of very specific numbers

Next, have a read of this article by everyone’s favourite podcast sponsor, the email marketing platform MailChimp:

  • Avoid Sales or Overused Words
    Most people know to avoid words like “free” in their subject lines because they trigger spam filters. But you should also avoid common words that are associated with sales, like “help,” “percent off,” or “reminder.” These words don’t always trigger a spam filter, but many subscribers will ignore them.
  • Include Localization
    Personalize a message with a recipient’s first or last name to improve open rates. MailChimp research suggests including a city name is even better.
  • Use Different Subject Lines
    Newsletters tend to start with high open rates, but these decrease over time. Keep your content fresh, and don’t repeat the same subject line for each campaign. If subscribers can’t tell something about your content from the subject line, they probably won’t open your campaign.
  • Keep Subject Lines Short
    Most people quickly scan subject lines to decide if they’ll open or ignore the email, so don’t expect subscribers to dig through your subject line to figure out if they’re interested. Keep your subject line to 50 characters or fewer.
  • Tone Down Promotional Emails
    Keep the message straightforward and avoid splashy promotional phrases, phrases in all capital letters, or exclamation marks in your subject lines. Subject lines framed as questions often perform better.

Campaign Monitor, another email marketing platform, have some great advice too about different approaches you might like to take, including this:

  • Personalization rules – It’s said that a person’s favorite word is their own name and now, we have the facts to back this up. Without a doubt, subject lines that are personally addressed, do the best – just don’t forget to test! Here’s more on subject line personalization.
  • Personal pronouns work, too – Don’t have your subscribers’ names handy? The popularity of “We” and “You/Your” shows that subject lines that make some kind of appeal to the reader are more likely to get a response.
  • Make it timely – Another trend to note is that subject lines that feature dates, or urgency seem to perform better than those that don’t. Holding your subscribers to a date to act, or letting them know that you’re waiting on them (with say, “Invitation”) can be a very persuasive tactic.
  • Be exciting! Finally, we noticed while doing this research is that subject lines that end with an exclamation mark tend to result in more opens than those that don’t. While we don’t encourage everyone to go overboard with enthusiastic exclamations (!!), it’s certainly interesting to see how a little extra energy in your subject impacts email behavior.

And, also from Campaign Monitor, these 8 great tips, summarised below:

1. The question subject line
Questions make great email subject lines because they get the reader to think about how the subject matter applies to their own life.

For example:

  • Do you check your emails when you first wake up in the morning?
  • Are you a zombie without your morning coffee as well?

2. The ‘How to’ subject line
The ‘How to’ subject line formula works so well because it forces you to describe the content of the email in very clear language.

Take these 3 subject lines for example:

  • How to get better marketing results through beautiful design
  • How to win friends and influence people
  • How to get 1,000 new email subscribers in 1 day

3. The scarcity subject line
Scarcity is a powerful driver of human behaviour. When something is in short supply, our fear of missing out kicks in and we are compelled to act.

For example:

  • Only 2 days left to get 50% off shoes
  • Hurry! Only 3 consultation spots left
  • Get free shipping if you order within the next hour

4. The announcement subject line
Using words like “Introducing” and “New” in your email subject line gives the reader a feeling that your email contains new, breaking information they haven’t heard yet.

Examples include:

  • Introducing Canvas: A better way to send emails
  • Update to our iPhone App
  • See our new design gallery

5. The number subject line
Every time we A/B test our blog post headlines, we find that the version of the headline containing the number outperforms the one that doesn’t.

For example:

  • 30 ways to build your email list
  • 3 steps to sending beautiful email campaigns with Canvas
  • 10 product announcement emails reviewed for conversion

6. The curiosity gap subject line
Professor George Loewenstein coined this term to describe the gap between what we know and what we want to know. When we notice a gap in our knowledge, it produces a feeling of deprivation that prompts us to go looking for that piece of missing information in order to stop feeling deprived.

For example:

  • Dave Richardson asks the most basic question ever, and stumps our smartest politicians
  • This little-known copywriting trick will increase your email click-through rate
  • 9 out of 10 Americans are completely wrong about this fact

7. The surprise subject line
Everybody loves a good play on words or a pleasant surprise. In fact, studies on brain activity show that these unexpected occurrences light up the pleasure centers of the brain.

Some examples include:

  • Warning: Unattended items in your shopping cart may be eaten by gnomes
  • What Elvis Presley can teach you about email marketing

8. The personalized subject line
Working your subscriber’s name into the subject line of your email adds a personal touch that is likely to catch your reader’s eye.

For example:

  • John, are you a zombie without your morning coffee as well?
  • John, 9 out of 10 Americans are completely wrong about this fact
  • John, there’s only 2 days left to get 50% off boots

And finally, here’s an infographic packed with yet more advice on killer email subject lines from Litmus:

This entry was posted in Behavioural Design, Brand Copywriting, Digital, eCommerce, Email Marketing, Hotfoot, Infographic, Marketing and tagged , , , , , , on by .
Relevant Pages: Email Marketing, Marketing & Brand Strategy

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