Does Email Subject Lines Increase Click Rates?

Email marketing is a popular way for businesses to contact prospects. It is also arguably the most cost-effective marketing communications. The email has some characteristics that make it a competitive tool for marketing. It is highly customizable. It is targetable. And it is flexible. Besides these points, a major factor to consider is that almost everyone uses email as a tool for both personal and professional use. And, in comparison with direct marketing, email marketing can capture interest and information via gated landing pages where people can submit a form to ask for more information, to ask to be contacted, or to register for an event, apart from many other possibilities.

Email for marketing

Standalone email marketing is now part of multi-channel campaigns. Besides, email marketing allows small businesses to have access to a powerful marketing tool to compete with larger organizations. That is why many marketers are relying on email marketing as a foundational piece of their strategy. Moreover, in business to business communications, it is mandatory to get permission from prospects to be contacted for marketing purposes. Therefore, recent data privacy regulations have made the email marketing environment secure and subscribers feel protected from being contacted.

Unopened emails

The number of emails sent each day is growing year after year. Therefore, nowadays the overwhelming number of emails that a person receives makes the recipients prioritize some emails over others and even leave many of them unopened altogether. The criteria used for prioritizing emails include, among many others, looking for a known sender and looking at the subject line. These are the critical components when deciding whether to open the email or not.

Email subject line

The usual email subject line gives legitimacy to the message when something personal about the recipient is mentioned. Some tests looked at survey responses with different email subject lines. There was no difference between generic email subject lines and customized subject lines. However, an analysis conducted in messages posted in forum newsgroups discovered that a question mark can increase the probability of a response. The common trait of successful subject lines is to have about 3 to 14 words. In comparison to previous academic and forum studies, using the company’s name has yielded positive results regarding the engagement rate of the emails.


Studies connecting email subject lines to engagement rates is scarce. Even in the limited studies available, researchers have not addressed the use of the subject line in detail. And, they do most of these studies in either user forum scenarios or academic settings. As we all know, results obtained from theoretical studies can be different from practice. All in all, there is a lack of academic research on the link between subject line and response rates. So, the email response rate depends from one company to another. What works for a company may not necessarily work for another.


Teiu, C., 2020. Email Subject Lines Analysis for High Open Rate in Email Marketing. In: R. Pamfilie, V. Dinu, L. Tăchiciu, D. Pleșea, C. Vasiliu eds. 6th BASIQ International Conference on New Trends in Sustainable Business and Consumption. Messina, Italy, 4-6 June 2020. Bucharest: ASE, pp. 835-840