With over180 billion emails sent and received worldwide every day in 2013, it’s fairly safe to say that today’s average inbox has become a veritable jungle of emails, some wanted, and some unwanted. And if you consider that it takes just mere seconds for most of us to scan our inboxes and decide which emails to open, which to “save for later” and which to delete without even reading, then it’s understandable that the battle for our limited inbox-attention is one of the email marketer’s biggest challenges.

Here’s the thing about typical opt-in subscribers: If they’re inclined to subscribe to a newsletter in the first place, then it’s highly likely that they have subscribed to more than one, so as an email marketer you’d do well to presume that your competitors are vying for your subscribers’ attention just as fiercely as you are. And since today’s typical subscribers are time-poor and bestow their brand-loyalty selectively and sparingly, only the cream of email marketers will rise above the others in their ongoing quest for a guaranteed email “open”.

So what can you do to out-open your competition?

For starters, you must deliver highly relevant, interesting and useful content. If you consistently send content that subscribers find valuable or entertaining, chances are that they’ll grow more inclined to open your emails as a matter of habit (a.k.a. “email marketing nirvana”).

But even if a subscriber likes your brand and enjoys your content on a regular basis, some days his inbox is so overflowing that the sheer volume of unopened emails is enough to turn him off opening any of them. And since you never know if you’re going to catch your subscriber on exactly such a day, you need to presume that every day is such a day. That means that you can’t ever rest on the laurels of your content alone, you also need to gate your email content so attractively that your subscribers won’t be able to resist a peek at it.

That “gate” is your subject line, and mastering the art of writing effective subject lines is therefore one of the most important keys to boosting your email open rates.

Here are some tips on how to write subject lines that are irresistibly inviting:

1) Be different.

Be different

If you haven’t already done so, subscribe to your competitor’s newsletters. After a week or two you should be able to get a good sense of the most common types of subject lines they use. Then, review your own subject lines and see how they stack up: Do they sound just like all the others? If they do, then it’s highly likely that they’re getting lost in that messy message jungle. What you want is to stand out by giving your subject lines an edge that the others don’t have. You may need to experiment with your subject lines to figure out what type of “edge” converts best with your audience (perhaps some of the tips below may help) but if they don’t look like all the others, then that’s already a good start.


Make one piece of content the “star” of your subject line.

Make one piece of content the "star" of your subject line

Ever heard of the term “content overload” or “information overload”? Of course you have, because you’re living in the twenty-first century and not under a rock. Your subscribers are already overwhelmed by the amount of content in their inboxes as it is, so they certainly don’t need to be bombarded with too much information in a single subject line! Too much information in a limited amount of space can be daunting to read, plus  it could also come across as “frenzied”, almost as though the sender is trying to cram the whole newsletter into the subject line itself for fear of the subscriber deciding to skip it.

Subscribers respond well to content when it’s presented with clarity and a sense of importance, so make things easy for them by simplifying your offering. Your newsletter may well contain more than one piece of content, but for maximum effect try picking the one item you care about most and make it the hero of your subject line.


Make your subscribers curious.


Sometimes, spelling things out directly is the most sensible strategy, but in some situations a little intrigue can be a powerful motivator to dig deeper. Using a little cryptic mystery in your subject line can be so tantalizing (if done well) that your subscriber literally won’t be able to resist opening the email to see what it’s all about.

A caveat about this tip though – if you’re going to use the ‘curiosity tactic’, be sure to live up to the implied intrigue in your email content. If you “cry wolf” too many times by implying something promising in your subject line only to under-deliver once the email is opened, this tactic will lose its effect.



4) Be quirky or funny.

Be funny

Let’s face it: The average inbox isn’t exactly the stuff of fun and laughter. When we see a bunch of unopened newsletters in our inbox, we know that they contain some sort of offer or marketing message (such is the nature of email marketing, after all) and usually we approach them already bracing ourselves for a predictable marketing pitch. So when we come across a subject line that’s unexpectedly funny or truly clever, it’s like a breath of fresh air an otherwise dull and predictable inbox.

When a marketer has clearly set out to make us laugh in an effort to take away some of the mundaneness of our daily email-opening routine, the moment that the corners of our mouths begin to form a smile or blurt out a giggle is the moment that our inclination to open the email multiplies exponentially, if for no other reason than to reward the marketer’s effort to entertain rather than bore us. Humor goes a long way (good humor, that is!).


Make it urgent.

The clock is ticking!

If your message is time sensitive or if you have something to promote that your subscribers would find valuable and would be upset to miss out on, then adding an element of urgency to your subject line is appropriate and can be very effective. No one wants to miss out on something truly worthwhile while there is still time to take advantage of it. A few caveats to this tip though:

  • Use it sparingly. If you use the element of urgency too frequently, subscribers will learn to anticipate that most your emails seem to be urgent, and once urgency becomes the norm it will lose its effect.
  • Use it honestly. Don’t abuse the element of urgency by applying it to promotions that aren’t all that urgent, because this too will ruin the effect for promotions that genuinely are urgent. Something that may seem like a priority for you as the promoter may not seem so urgent to your subscribers, so consider carefully whether the element of urgency is truly appropriate before you use it.
  • Be creative, not predictable. Remember that you are not the only marketer who has something urgent to convey to his subscribers. So many subject lines these days begin with repetitive frenzied pleas (like “Don’t miss out!”, “Last chance!” and the all-annoying “Hurry!”), that not only have they become ineffective due to puke-inducing overuse, but they also scream of the marketer’s desperation, which is even less appealing. These types of predictable subject lines are so frequent that instead of increasing the sense of urgency they actually diminish it.  After all, why should subscribers rush to “act today” if they can count on a steady stream of more “Urgent!” emails arriving in their inbox at regular intervals anyway? So to give credibility to the element of urgency in your subject lines, be creative and try to stay away from the irritatingly clichéd and overused calls-to-action.


 Make it conversational.


Back in the early days of email marketing, subject lines often sounded either formal or terribly professional, probably because marketing emails were still regarded as just another form of “correspondence via email”. Happily, we’ve loosened up a lot since then thanks to the advent of about a million new messaging options that call for virtually no formality at all, and this informality has trickled into our inboxes too.

When we send and receive emails, we are after all just people trying to talk to each other, right? So sometimes the best way to connect with a subscriber in the subject line is to say what you want to say as though they were right in front of you. A conversational approach makes you sound more accessible and makes the subject of the email sound more relatable.


 Make it controversial.

Ever come across a well-written teaser for a juicy piece of news or a provocative statement that didn’t make you want to learn more about it? If your answer is “no” then either the teaser wasn’t well-written or it wasn’t written in a language that you can read.

Subject lines that are based on a bold or interesting statement or on something that sounds controversial are a great way to pique a subscriber’s curiosity. But as with the caveats for some of the tips above, this is another one that should be used sparingly. If too many of your subject lines sound controversial then eventually your subscribers might start thinking of you as nothing more than an attention-seeking drama queen!


 Make it strike a chord.

Thumbs up!

The best email marketers know their audience well enough to understand what makes them tick, sparks their interest and inspires them into action, whether it’s a common concern, goal or interest. If you can make your subject line relatable to your subscribers so that they feel that you really “get” them, then this instant affinity can be just the thing that inspires them to open your email and check out the rest of your message.


 Don’t make it too “salesy”

Pushy Sale

Retailers have it particularly tough when it comes to email marketing because most subscribers assume that virtually every email they receive from a retailer is an attempt to sell them something. And since the average inbox contains its fair share of retail emails, the average subscriber can sometimes feel overwhelmed by a barrage of subject lines from multiple retailers all aiming straight for his wallet.

Personally, I now routinely avoid emails whose subject lines appear too “salesy” because I reserve the right to open emails that are clearly attempting to sell me something only when I feel like shopping, not whenever the brands I subscribe to want to shove their products down my throat simply to meet their daily sales targets. Instead, I like to open emails whose subject lines hint of interesting content or of products that I might want to learn more about. If there happens to be a sales pitch somewhere alongside this content too, at least then I’m actually exposed to it, so the marketer has achieved his goal even without being blatantly “salesy” in the subject line.

I don’t presume to speak for all subscribers of course. I’m sure there must be someone somewhere whose biggest thrill in life is an avalanche of daily sale emails, but if as a marketer you care about the sanity of the rest of us and understand the merits of selling in moderation, you should apply this philosophy to your retail emails too.

As I said in Tip #5 above, there are only so many subject lines containing the words “40% off!” and “Sale!” that a typical subscriber can be subjected to before it permanently numbs his excitement over the opportunity to “save” because this opportunity repeats itself too frequently to truly warrant urgent action.


 Use ‘how to’, ‘numbered lists’ and ‘trending keywords’.

I know!

People appreciate an opportunity to learn something new about subjects that interest them, so ‘how to’ subject lines (like “How to write subject lines that get emails opened”) and ‘numbered list’ subject lines (like “11 killer tips to writing highly clickable subject lines”) are still effective despite their widespread use. Also, if you keep up with trending keywords that are relevant to your industry or your audience, using them in your subject lines can be a great way of adding timely and topical relevance to your messages, making them a lot more appealing to click on.


 Never over-promise, mislead or lie.

Don't lie

It seems redundant to expand on this tip so I won’t. Suffice to say that most of us have a very low tolerance level for email marketers who trick us into opening an email only to find that the content within isn’t even remotely relevant to the premise of the subject line.

As the ancient sages used to say:

“Open an email with a bogus subject line once – shame on the marketer. Open an email with a bogus subject line twice – shame on you!“ So don’t fib in your subject lines (ever).

NOTE: This post is also available as a presentation on Slideshare.


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