Best Practices For Optimizing Subject Lines in Your Email Campaigns


Writing the subject line for your newsletter may not seem as important as the content of the newsletter itself. However, this could determine whether your newsletter is read from the beginning. According to Invesp, 69% of all email recipients report emails as spam after reading their subject lines. Being marked as spam is the last thing any business wants after spending time, money, and effort on their email campaign.

However, hope is not lost! Let’s discuss subject-line best practices and why you should study your target audience to improve conversions and click-through rates.

What is the subject line?

When an individual receives an email, the subject line is the first text they see after their sender ID. As a result, the subject line of an email should be informative, compelling, and concise. If an email has an engaging subject line, half of the recipients will open it. Email receivers will only ignore your text if it is comprehensive enough or appears as spam, just like an article headline or a book title.

However, an email subject line must concisely provide relevant information. We know many emails can end up in the spam folder based on their subject line alone. The necessitates care and quality content from existing and new businesses  – no one wants their newsletter to end up in the trash folder without the recipient opening it. 

What is the foundation for creating forward-thinking subject lines?

Subject lines should be written to increase email deliverability and stand out from the crowd. Here are a few things to consider if you want to increase your email open rates.

Consider the style

Firstly, consider which subject line style you will embrace, depending on your target audience. An informational type would be ideal for busy and organized people who thrive on efficiency. Since time is always an asset for these readers, you must be clear and concise in your subject lines. Put important information in your subject lines to help them out.

A personal touch is another great subject line style. Personalizing your subject lines might help you captivate your readers from the start. In the subject line, you could provide the recipient’s initial name or any personal information, such as recent purchases.

On the other hand, creating a sense of urgency has been shown to motivate people to act. People are more likely to respond to the threat of losing something than to the promise of getting something. You may gain the same effect with your email subject lines.

Be brief

Smartphone use has rapidly grown as a result of technological developments. Almost half of the individuals now open emails on their phones – 46%, to be exact. Most individuals check their email while on the move since mobile devices are readily accessible.

When writing your subject line, you should keep your subject lines under 40 characters to avoid the text being cut off in smartphone inboxes. Moreover, remember that many readers will not read an email immediately if it doesn’t interest them.

Ask questions

Curiosity is vital, but it is most effective in articles. Regarding email subject lines, pose an important question and allow the recipient to click to view the answer. Try to refrain from beginning a statement in the subject line and continuing it in the body. It will be seen as clickbait and may lead to recipients ignoring your email or unsubscribing.

Filter for spam

Avoid using forceful sales copy and flashy formattings, such as all caps, or repeated punctuation, such as exclamation points. These will most certainly end up in the spam folder without the reader even opening them. Emails with the issues mentioned earlier can also be routed directly to the spam folder because they will immediately trigger spam filters from several mailbox providers. To avoid this, begin your subject line with other tactics and valuable information.

Why must the audience be studied to create a compelling subject line?

Studying your target audience is critical in creating a compelling subject line. Choosing what style would best engage your audience is only something you will know once you have learned what your target audience reacts best to.

A test is one method for discovering more about your target audience. With competent email marketing tools, you can perform A/B or split testing on your emails. This is where you send out two or more identical newsletters, with the sole difference being the first line.

From here, you can determine which newsletter had the most openings. It goes to reason that one must have had a more appealing subject line. However, you may monitor other variables, such as how many individuals unsubscribed or visited your website, to get a complete story of how effective your newsletter was.

When reviewing subject lines, you can experiment with various aspects such as length, question use, personalization, etc. Subject lines should be tweaked and tested regularly to understand what connects with your specific audience.

Another key move is to segment your audiences. People sign up for your newsletter for a variety of reasons. The offers may have drawn in some of them, while your content convinced others. Subject lines that may entice one group of recipients to open your email may only attract some of your readership. Write subject lines that appeal to several audiences using the same premise as A/B testing. You may discover that the combined open rate outperforms sending the same message to everyone. 


Subject lines are just as important as the content of your newsletter. By applying the best practices for optimizing your email subject lines, you can avoid falling into the spam trap and recipients ignoring your emails. Once you put the best methods to use, you will engage your target audience with a catchier copy whose success you can replicate again and again.