How to write subjects that will boost the open rates of your email marketing campaigns

di Alessandra Caraffa

When searching for digital marketing tips and trends, you shall pay the right attention to a little chapter of a whole new science about increasing your revenues, sales or customers: the one concerning the open rate of your emails.

It’s quite self-explanatory: if your messages don’t get to your target recipient, then the whole process of getting more prospects, clicks, sales - or whatever you’re trying to improve in your digital marketing strategy - will stop before it even starts.

That’s why one of the most important points to take care of, as an email marketer, is to have a good open rate for newsletters and campaigns. Here’s some good advice about how to write email subjects which can dramatically increase the open rates of your emails.

How to set up an email campaign that people want to read?

If you’re searching for the right strategy to make your contacts read your emails, then you shall begin your path from a quite basic analysis about your brand and what are you trying to do with an email marketing campaign. 

A well planned strategy starts from a clear and distinct idea of what we want to achieve and how we want to look while doing it - which is pretty important in inbound marketing.

So, there’s only one thing you have to do to improve the open rate of your emails: send messages that people want to read. It may seem an easy task, but every marketer knows how disappointing could be an attempt to make a campaign stand up among thousands of yelling emails going everyday around the globe. 

There are some recognised good practises that should be an assumption, if you want to improve the performance of your email marketing campaigns. Almost 35% of email recipients say to open messages based solely on the subject line. So, which features should your campaigns show in the subject lines?

  • Personalization: no one wants to read a message from someone he doesn’t know and don’t even call him by his name. A pretty effective routine you should really try, allowed by the most part of marketing automation software, is to address the recipient of your email using his name. 

Using the dynamic fields, you could send a different email to every single contact of yours: this will make your recipients feel more engaged from the very start of your interaction. The customization of the subject line could lift to a 29% increase the open rates of your campaigns (Experia). That is mostly true for triggered campaigns.

  • Responsiveness: in B2C as well as in B2B, more and more people read email on mobile devices. An average of 30% of business emails are checked on smartphones and tablets, and more than 50% of online purchases take place through a mobile device. 

This is a fact, and you cannot avoid to write emails which are responsive and suitable for different devices. This can affect the concept of your subject lines, though: the most used is between 30 and 39 characters, but if your purpose is to improve only the mobile email opening rate you should not exceed 30 characters. 

Anyway, this study from GetResponse discloses a far more important fact: the emails with the highest open rates have really more than 90 characters. So, the length of your subject line will not affect the open rate. A perfect responsiveness of your email could do that, though.

  • Reliability: if you want your newsletter to be read, you should not sound spammy or pushy. There are a few words you should avoid in the subject line, such as FREE, SALE, best price or big deal. Try not to be too selly, and focus on your prospect. 

You’re writing to someone who, maybe, is interested in your service, product or information. How to build a relationship with your contacts and get them engaged? Give them what they want to read: news, updates, guides, tips or a weekly video tutorial. The right CTA will do the rest. 

The first thing to know, if you really want to improve the open rate of your email campaigns, are these general rules for setting up an email marketing campaign which your target wants to read. This is a good starting point to go further and see how to boost the open rate of your emails writing the right subject lines.

How to write the perfect subject line for your email campaigns?

A good subject line should sound friendly and reliable, as we said. Here’s some tips you can take to improve the effectiveness of your email marketing strategy. 

  • Use the preheader: that’s a short line of text which the recipient can see as a preview of the email, just below the subject line. The preheader often corresponds to the first words of the message, so it is quite important to use them in an effective way: the right “summary” could really help the recipient get a clearer idea of what your email is about. 

A strategic use of the preheader can have a major impact on open rates: it can easily complete the subject line and pique your recipients curiosity.

  • Don’t use the subject line to sell: it’s not only a matter of reliability, but also a clear statement from today’s digital marketing trends. If you sound like someone aggressively trying to sell something, right from the presentation title of your message, you have less chances to get new audience. 

Email recipients receive hundreds of emails openly inviting them to buy, subscribe, get promotions and so on. Nowadays marketing is based on storytelling: try to use your subject line to introduce your audience to some kind of narration. 

You don’t need to put a CTA in your subject line: just use it as a title for your story, to persuade and captivate your audience.

  • Be specific: as said, the length of the subject line does not directly affect the open rates of your campaigns, actually being specific does. People don’t want to guess the content of your email, so try to be more specific as possible right from the subject. 

A vague or mysterious message could work in some situations, but that’s a specific strategy to apply to your email marketing praxis, which has to be suited for your audience and consistent with your brand. Especially in B2B campaigns, being specific is a must. 

  • Create urgency: a classic of traditional marketing, still working perfectly. The so called FOMO (Fear Of Missing Out) can still generate a 22% higher open rate (HubSpot). Alluding to a quite close deadline for taking the advantage you’re offering can lift your open rates, especially in ecommerce business and in triggered emails campaigns.

A narrative, clear, never openly pushy design can define the perfect subject line. It is obvious, though, that the perfect subject sent to the wrong person would still come to nothing. Your email, such as its subject and its preheader, should be tailored to fit a particular segment of your target. That’s why personalization, responsiveness and reliability were previously put as assumptions.  

Some other tips about subjects 

Once you’ve made your studies about the segmentation of your lists, the setting of the right tone for your brand and the identification of potential flagship products or services, then you can take the following tips to write an outstanding subject line, which can complete a proper and effective email marketing campaign.

  • Go with A/B testing: the split or A/B testing is becoming a must for digital marketers. Once you’ve segmented your lists, you should go on determining a sample of recipients to use for this kind of testing. 

Especially useful for the improvement of subject lines and graphic design, A/B testing consists in sending slightly different versions of the same message to the same recipients, and compare the effectiveness of every version. 

This is a unique practice, for it allows you to test single word efficacy such as the impact of your tone of voice in opening rates.

  • Try emojis (if that fits your audience): that’s the latest trend of B2C email marketing, as you can easily guess while checking your email inbox. It can work quite well, but it has to fit your brand, your purpose and your audience. 

A study from Experian reveals that subject lines with emojis can reach 56% higher open rate. Other studies indicate an increase of unique openings by 29% (ReturnPath), and some divide data based on the target audience age, linking the prolific use of emojis specifically to millennials (GrowthHackers).

  • Use a pinch of negativity: it may sound weird, but a wise use of negativity can increase the open rates of your email campaigns, in B2B and B2C marketing operations. Based on a study of the marketer Derek Halpern, negative subject line increased his open rate by 35%. 

So, negativity works for the news as well as for selling. You could sound a bit negative while inviting your prospect not to lose an opportunity or the right timing, for example. That’s the typical experiment to test with the A/B method. 

  • Include numbered lists: The presence of numbered list in your subject line, especially if you’re sending an email series, can help dramatically the increase of your opening rates. That’s because one of the things people want in their email inbox is easy solutions to complex problems.

The structure of the numbered lists give confidence to the audience, and can help increase your open rates even in B2B campaigns. 

  • Test perseverance: you’ll never say, but it is a fact that a recipient who does not open your messages on first submissions, may open it on following attempts. The power of A/B testing is quite evident in such cases: send a message to your testing segment, and after a week try to send the same email with a different subject line, or a modified preheader, or in a different time of day. 

You’ll be surprised how well this practice can work.

A long-term email marketing strategy is fundamental: no matter what the specific sector of your business is, you cannot avoid email marketing, and the starting point for an effective email marketing strategy cannot be but a good open rate. So, try some of the tips above and test them. There might be surprises.

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