Basic Guidelines for Subject Lines

1. Keeping it Brief – The 2-2-2 Principle

The principle that would be on the first page of Mobile Email for Beginners. The first 2 stands for the two seconds of attention you get from a prospective reader, the second 2 represents the first two words of your subject line that grab the reader’s attention and the final 2 stands for the ‘to’ in ‘today’ – as in the relevance the subject line has to the reader today. Catchy isn’t it?

2. In a Land of Ambiguity, Relevancy is King

A study by the fine folks at Alchemyworx states that while longer, ambiguous subject lines do have higher open rates (especially on desktop), they don’t have a higher ‘click to buy rate’ – in fact they most likely have a higher ‘annoyed consumer rate.’

It’s not all bad news though! They also found that shorter, more concise subject lines that are transparent about the contents of the email (such as ‘50% off Nike’) find more success with a 60% of opens turning into click to buys! This information is perfect for the mobile marketer as longer subject lines simply do not translate well on smaller screens. Keep it real, relevant and short.

3. Curiosity Creates Clicks

Know your objective. Unless you’re sending out chain letters, your emails have a point. In addition, no one is going to open your email if no-one cares about your objective. How do you get people to care you ask? You create curiosity.

Curiosity may have killed the cat, but that was only because the owner was too busy buying stuff online. The perfect kind of curiosity is the type that isn’t ambiguous yet still requires the reader to act. A great way to do this is to provide provocative adjectives about a topic in the mail itself. For example, if you want to sell cat toys a good subject line would be “Unique Toy for Whiskers.” The adjective in the subject line begs the reader to inquire about what is so unique about the toy for their cat.

4. Assume a Personal Stance

The majority of intriguing subject lines assume a personal stance.

While this includes using personalization, it doesn’t stop there!

These subject lines typically assume that you’ve had personal or business contact with the company or sender before. They accomplish this by using your name, referencing an action (real or implied), using informal language, or thanking you for something, to name a few.

So, for an email introducing a new product or service, the following subject line wouldn’t get many opens: “New Series of Kettles.” However, when we apply just the first trait of interesting subject lines, we get something much more appealing: “We couldn’t have done it without you, Mark!”

Not only does this imply previous action, uses a personal name and expresses gratitude, but it also piques curiosity begging the reader to ask, “what on earth did I do?”

The answer to this question could be that thanks to the recipient’s loyal patronage to the company, the brand is able to launch a new series of products.

Check out these examples of the best words to use in a subject line.

5. Inspire a Response

Do this even if you don’t monitor actual responses at all.

Naturally, when we feel we need to respond to something we engage with the material first before sending out our response. This is exactly what an email marketer wants recipients to do – engage with their material (email)!

If an email is able to evoke a feeling of need within the recipient, they’ll find a way to resolve that need – usually through interacting with or at least reading through your email.

You can encourage response by phrasing your questions or statements towards one person and expecting a response. Make it sound like it’s completely natural for your recipient to respond or use ‘action words’ such as act, download or participate to get your reader to act.

For example, “Download this and Change Your Perception” or “Is This What You Really Think?” of these sound like the sender expects the reader to respond or act. Incidentally, they all do a great job at sparking curiosity as well, which is another plus!

You have to know what you’re doing right in order to improve, so tracking these responses by using reports is just as important as getting the responses.

6. Imply Exclusivity and Scarcity

Everybody has an inherent desire to be unique. Scarce and exclusive objects help satisfy this human desire – which means that a scarce or exclusive product is valued much higher than objects that aren’t!

Using words such as ‘exclusive’, ‘one-time’ or ‘limited’ are just a few ways to get across that your product or offering is something valuable.

If readers see value, they’ll turn into value for your company.

7. Expressions and Emotional Reactions

The more you identify with your target market and convince them that you’re not simply a machine looking to take their money, the better off you’ll be.

A fantastic way to convince someone that you’re human is simpler than you thought: act like one!

Display strong emotions in your subject line that people can relate to. Disbelief, happiness, excitement or even sadness can work to your advantage, as long as you bring it down to a personal level, rather than trying to impose it on your recipients.

For example, focus on raising a question that has strong emotional ties, like “I can’t believe I’m doing this…” This raises the obvious question of what, and has a strong emotional tie to it – that of disbelief, which is something all of us can relate to.

On the positive side of the spectrum, you can use something simple, for instance, “This is what gets me up every morning.” Here, you’re implying a question as well as offering value to your reader in the form of exclusivity (as it’s implied that only you know this little fact that starts your day).

8. Spin It!

Remember – after the subject line and snippet, your email content has to be consistent! It’s easy to tie in your subject line with your content anyway you like.

Maybe offering amazing deals on car washes gets you up every morning, or you can’t believe that you’re about to slash 10% off on all winter clothes – by then your subject line will have done its job and it will be up to your content itself to convert!

In addition, you could always use A/B split tests to find the subject line that has the best response!


  • Author: maryka.burger

  • Maryka has worked across multiple industries ranging from hard news journalism to digital tech companies and advertising. She is an expert at building online presence, and offers a wealth of knowledge on digital marketing, social media and automation trends to agencies and digital start-ups.