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Email subject tips on how to write

Email subject: tips on how to write

Email subject is the reason why you and everyone else select a message among many others in the inbox.

This part of the email is critical for those working with email marketing. Depending on the subject line, your open rates increase, and this is the bridge that will lead to conversion.

However, even before people open the emails, they need to be available in the inbox.

Did you know that an unverified email list can be completely blocked by providers? This happens because emails with errors are tagged as spammers if the quantity of bad addresses reaches 3% of the base.

Thus, email verification is a priority for campaigns to reach recipients. With validated emails, it’s time to create an irresistible email subject.

In this sense, check out the tips we’ve prepared for you to create amazing subject lines!

1. Be quick

Our eyes take between 3 and 4 seconds to send all the images from the inbox to the brain, so that the emails to be opened are selected.

In other words, it means that a well-crafted subject line should catch users’ attention in that time. If the goal is achieved, the reader opens the email.

Also, note that the email subject space has a limit of 50 characters, to ensure full viewing by readers, regardless of the device they are using (desktop, mobile, or tablet).

Now that you know you have a small space to insert the call, create a subject that appeals to your persona’s emotions. Let’s see how to do it below.

2. Personalized and non-transferable email subject

Personalization is a trump card of digital marketing. It is through it that senders get closer to leads.

Email marketing is the ideal tool for working with personalized communication, as we can insert the lead’s name in the subject line.

However, in addition to the reader’s name, the email subject can have more personalized items, making the user truly identify with what is being said. See some examples:

  • Name + persona’s pain. Ex.: [Paul], [overcome depression] in no time.
  • Name + persona’s goal. Ex.: [Paul], [get an MBA] at University XYZ.
  • Name + persona’s niche. Ex.: [Paul], see what [gamers] recommend.
  • Name + persona’s company name. Ex.: [Paul], [working at Petrobras] gives you advantages.
  • Name + persona’s work sector. Ex.: [Paul], [project managers] like this.

Note the importance of knowing the persona you are working with well. Understanding their pain is no longer enough. It is necessary to have knowledge of everything that revolves around them. Every piece of data is relevant.

Learn more about subject lines by watching our webinar!

3. The right-hand man of the subject line

The email subject is accompanied by a piece of text that appears next. This space is called the preheader, and its function is to assist the email subject.

In other words, the email subject is the call, and the preheader is its continuity.

We saw that a well-crafted call should not exceed 50 characters. The preheader, in turn, should have a maximum of 55 characters.

Thus, complete visualization of the email subject and its continuity is guaranteed on any device.

4. Ask questions

Using a question in the subject line can generate interest in the reader. This is linked to curiosity, which is a natural human feeling.

The curiosity trigger is important for decision-making because it drives the consumer to know more and better about your product or service. And if the argumentation is good, conversion occurs.

The concept of personalization combined with the curiosity trigger forms a highly effective copy tool.

5. What is the best keyword for the email subject

Knowing the persona well represents countless advantages for the success of an email marketing campaign.

By identifying preferences, emotional state, and other information about the email recipient, it is undoubtedly easier to work with words that can awaken the desire in them to open the message and move forward.

It is important to highlight that the referred keywords are those relevant to email marketing communication, not those related to Google’s search system (SEO).

6. Email subject – how to test

A/B tests are simple and ensure an assertive campaign. All this optimizes ROI in the end.

To test the subject line, create two call variants. Select a number of recipients and segment 50% to receive one call and another 50% to receive the other subject line.

In conclusion, the message (email subject) with the most openings will be the one to be sent to the rest of the base.


What does the email subject have to do with the open rate?

The subject line is the first visual contact the recipient has with the message. Among several emails in the inbox, the call is the differentiator that will engage the reader in communication.

Therefore, the more persuasive the email subject, the higher the open rate, optimizing conversions and campaign ROI.

How does the brain select an email from among many available in the inbox?

A person takes an average of 3 to 4 seconds to view the inbox and select the emails to be read. Thus, a subject line has this time to fulfill the function of catching readers’ attention.

Why should the subject line and preheader have few characters?

The space for the subject line should have up to 50 characters, and the preheader should not exceed 55 characters. This is the ideal space for complete viewing of the call on all devices (desktops, mobiles, and tablets).

What is the difference between a personalized email and a common email?

A personalized email activates the persona’s mental triggers. Thus, conversions are enhanced.

Why is it interesting to ask questions in the email subject?

To activate the curiosity trigger, which drives the reader to decide to open the email and learn more details.