Thinking of what make subscribers open your marketing mails?

Well, all your answers would echo around many factors.

But, I know you all would agree with one point, that determines the opening of emails i.e. – Subject Lines.

The famous saying related to email subject lines states that –

If Your Email Subject Lines Are Of High Class, Then No One Can Stop You From Getting Success In Email Marketing.

So now you know  how powerful subject lines are.!


A study on email subject line done by MarketingSherpas claims that – A right subject line can increase open rates up to 12.7%.

So, now let’s begin with discussing the “Dos and Don’ts” of making eye-catching email subject lines.

As said –

A list of recipes can’t make you a perfect chef, until you don’t know how to cook them.

But before beginning, have a look on the below infographics –

Got an idea of What To Do and What Not To Do.. ? we can

Let’s now move on to How To Do It part –

The Dos : What Your Customers Love

1. Do keep it short and simple :

Studies reveal that a subject line between 4-15 characters has the highest open rate (15.2%; MailerMailer report), whereas the maximum length of email subject lines should be not more than 60 characters.

A short subject line will be displayed fully on mobile phones too and guess what around 66% of the people use mobile phones to check emails (Marketing Land Report).

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See what PayPal does, only 16 characters and I think you clearly understood what it wanted to deliver.

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Now for keeping it short hyphens, colons and semicolons could be a great help. Twilio smartly uses a colon to reduce the length and at the same time delivers the message fully.

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So give what it takes, but use short subject lines in your emails.

2. Do tell user what’s inside :

Tell your user what you’ve got for him straight forward. Don’t waste his time or you may find your email moved to spam or trash.

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In the subject line above InkThemes is offering a huge 85% discount. Now as the reader is sure what he is getting inside, if he opens, he is ready to buy.

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3. Do keep same text in subject lines :

Keeping similar subject lines in a particular series of mails makes reader used to those particular emails. And if a subscriber gets satisfied with a single email of the series, he’ll definitely see the rest too.

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I’m not asking you to copy paste the same subject line every time,but atleast 3-4 words should be same so that it links properly to the previous one.

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The above subject lines are of Canva which is a graphic design software. All of its emails start with subject [DESIGN 101] which brings consistency and continuity in marketing of their products through emails.

4. Do ask Reader to perform an action :

Motivation works. Give a call to action and people would respond. Below examples illustrate howto ask a reader to perform an action.

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You need to smartly blend your information with a call to action, to get more opens while practicing effective email marketing.  

5. Do invoke emotions (but not unnecessarily) :

An Emotional touch (joy, excitement, love, care) always works for a subject line. Check out the example below.

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As soon as one reads the words “Happy Holidays”, the emotion drives him and he opens your email.

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But hey, using emotions unnecessarily could be worst, be very careful with this. Give what you promise, or else no trust next time.

6. Do ask Questions :

You grow up answering everyone, to your teachers, your parents and everyone else around you. Its has become a habit and this might be the reason why asking questions in subject lines works.

Check out the examples below and see how differently questions can be asked.Subject line 13

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7. Do be creative :

For good email marketing, creativity counts, its something that’s always appreciated. Now, creativity doesn’t mean you beat around the bush, you can be creative and straightforward simultaneously.

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A small phrase “A splash of red” has enhanced the subject at the same time hasn’t altered the meaning. Check some more examples.

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Happy turns appy, attracts you and invokes your interest.

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8. Do be Useful and Honest :

Your marketing email would only be opened, if the email subject line states it useful. People are very busy and only interested in emails that can actually help them.

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Try to make your intentions clear in the subject line itself and maintain it till the “click here ” button of your email. This will help you in long run,I bet.

9. Do test, test and test :

I’m contradicting myself, but all the above practices may sometime fail, but what will definitely succeed, is testing. A/B testing is a tool used by numerous email marketing services today, where you make two subject lines and send to two different groups; the one with more opens is the winner.

US president Barack Obama raised a whopping $60 million additionally, using A/B testing (Source: Event360). What more you need to trust me on this now.

10.Do Proofread :

Even if you write a single word subject line, do cross check it a couple of times. A misspelled word is a red flag in your email’s reputation. Be alert of this.

The Don’ts : What Your Customers Hate

Don’ts don’t need explanations, you just need to avoid following the below mentioned practices. Study of much of researches and analyses on writing professional subject lines have led me to find out and produce to you these non-practices.

Still for your better understanding, we will discuss so as to why one should avoid doing them.

1. Don’t use FW: or RE: to misguide people :

Just to imply that the email has come from a trusted source, don’t use such words. The reader will find it eventually and then your email reputation is at stake.

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Tell me who gives a reply of “Last Chance to Save 50% Off”. No one is gonna open such emails then or ever.

2. Don’t write in all caps :

It takes less than a fraction of a second for a recipient to decide whether to open the email or not. You need to leave no stone unturned to grab his attention.

But that doesn’t mean YOU CAN SHOUT ON HIM. Using all caps can turn him off and you may filtered to spam.

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3. Don’t include exclamation marks :

Using exclamations have the same effect as the caps, it feels like you are forcing your email onto someone. Believe me, a reader doesn’t need any of it. Don’t make a subscriber feel you are desperate, be genuine.

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4. Don’t use spammy words :

It’s 21st century, people are smart enough to judge your envelope from its cover. Including words like Free, Guarantee, Visit our website, etc may trigger spam filter and if not, the reader himself may spam filter it. These all are red flags, avoid using them.

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5. Don’t use symbols or strange characters :

Don’t use symbols if you don’t want your emails look cheap and spammy, because a standard email from a reputed source always has its elegance and grace.

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Symbols may also trigger spam detectors and booh your email is in the spam before a user may even look at it.

6. Don’t use sales language :

Cheesy sales pitches are a big turn off for subscribers. Their instincts don’t allow them to open emails, subject lines of which simply advertise products or services.

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Tell but don’t sell.

7. Don’t use misleading subject lines :

Misleading email subject lines lead nowhere but to unsubscribe. And according to CAN-SPAM Act, writing such subject lines is illegal.

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In the above example, who can tell what the email wants to convey, moreover the word Facebook misleads you. You need to be careful and shouldn’t follow such practices.

8. Don’t use your recipients’ names :

They know their names, why should we recall them. A name in your subject line not only increases its length unnecessarily but also negatively impacts the open rates (A MailerMailer study).

9. Don’t be too mysterious :

Too much mystery can kill the thrill. You should write effective email subject lines that generate curiosity but not mystery.

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10. Don’t send emails asking help :

Emails asking help don’t open, as people fear of being scammed. Try not to always crying wolf, instead send emails that offer help to readers.

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This was the first installment of the series, Email Marketing Best Practices which focused on writing subject lines.

I hope by now, you have got a good understanding of writing email subject lines that work, still if you are stuck at any point anywhere, feel free to ask at [email protected].

Do you think some more things need to be added in this post, do share in the comment box below. Will be back with something more interesting on email marketing soon…