52 Email Subject Line Statistics: 2024 Trends & Effective Ideas

In business practice, subject lines can make or break a marketing or promotional email, a job application email, or a newsletter. They are so crucial that many research efforts have been made just to find the right formula for subject lines.

In line with these, we have prepared the following email subject line statistics below for you. These offer insights into what elements make subject lines work and what you should not do to avoid getting sent to the spam folder. After going through these, you can make better use of your email marketing software.

General Email Subject Line Statistics

The importance of the email subject line is often stressed in email marketing. After all, 47% of email recipients decide to open emails based on the subject lines alone. If the subject line does not pique their interest, they will delete the email automatically. Or worse, report it as spam.

• 69% of email recipients report emails as spam after reading the subject line. (Invesp, 2021)
• One research reveals that 33% of email recipients open emails because of catchy subject lines. (OptinMonster, 2020)
• Another study shows that 64% make a decision to open emails based on subject lines. (Barilliance, 2021)
• A similar survey reports that 33.90% of recipients open an email because of the subject line. (SuperOffice, 2021)
• A/B testing of their subject lines led Skandium to increase their CTR by 26.96%. (Barilliance, 2021)
• 47% of marketers test subject lines before finalizing their emails and sending them out. (HubSpot, 2019)
• Malicious emails contain the word “invoice” in the subject field 13.2% of the time. (Statista, 2020)
• The term “mail” appears in the subject line of 10.2% of potentially harmful emails. (Statista, 2020)
• The United Kingdom has the highest share of malicious spam containing the word “coronavirus” in the subject (20.8%). (Statista, 2020)
• Email subject line personalization is used by 34% of marketers in the US and the UK. (Adobe, 2020)
• 82% of marketers send emails whose subject lines do not exceed 60 characters. (Convince & Convert)

Newsletters

Newsletters are an integral part of marketing and promotions. However, there are many instances when recipients do not open the newsletters or delete them outright. Help from email subject line examples and the following statistics offer insights into what you should or not do with your newsletters’ subject lines.

• Emails that have “Newsletter” in their subject lines decrease their chances of being opened by 18.7%. (Invesp, 2021)
• Including the word “alert” in your newsletter’s subject line increase open rates by 61.8%. (OptinMonster, 2020)
• Beware of “you” in subject lines because it can decrease open rates by 5%. (OptinMonster, 2020)
• “Request” is the most frequently used term in BEC email subject lines. So that is a word legitimate organizations must avoid in newsletters or marketing emails. (Agari, 2019)
• In Italy, newsletters with 10 to 20 words have open rates of 35.5%. This reiterates the observation that the fewer words, the better. (Newsletter2Go)
• Germany has the highest open rate for newsletters at 40.67%. (Get a Newsletter, 2019)
• Singapore logs the lowest newsletter open rates at 11.89%. (Get a Newsletter, 2019)
• The average open rate for newsletters across all industries is 21.33%. (Backlinko, 2021)

Subject Lines Statistics for Job Seekers

A person who is job-hunting must have a good email subject line for job applications. That is something one should not forget because the open rate of emails with no subject lines is only 8%.

• 47 out of 100 hiring managers ignore emails with spam-like, generic, or anticlimactic subject line. (CareerAddict, 2021)
• Including the recipient’s name in the subject line may up the chances of the hiring manager opening your email by 20%. (Marketing Dive)
• Subject lines with 6 to 10 words have a 21% open rate, which is the highest. (SuperOffice, 2021)
• Subject lines with the first word capitalized have a 16.7% open rate. (Inntopia, 2021)
• Avoid ALL CAPS—these garner zero opens and are likely to get your email sent to the spam folder. (Campaign Monitor, 2019)
• Exclamation points may work for marketers but they may not be successful in job application emails. Emails with exclamation points in subject lines have a 45.5% open rate compared to the average of 51.9%. (Ladders, 2020)

Effective Subject Lines Statistics

What makes an effective subject line? It is a mix-and-match of crucial factors. Often, it also depends on the disposition of your audience. To put a finger on the pulse of your target market, it would help to conduct A/B testing using email marketing solutions.

• Only 44% of ecommerce companies include offers in email subject lines. (Tidio, 2020)
• Discount-based offers on subject lines have a below-average performance at 38.31%. (Klaviyo, 2019)
• Emails with the recipient’s name on the subject line have an 18.30% open rate. (Invesp, 2021)
• Those that do not have names on the subject line only have a 15.70% open rate. (Invesp, 2021)
• Including the word “Free” in the subject line were 10% more successful in being opened. (Invesp, 2021)
• Including a sense of urgency and exclusivity in subject lines give emails a 22% higher open rate. (Invesp, 2021)
• 50% – the increase in open rates of emails with personalized subject lines, another study shows. (Marketing Dive)
• Interactive subject lines have 70% higher conversion rates. (Jeff Bullas’s Blog)

Much Ado About Emojis

Some marketing professionals swear that emojis in subject lines boost email open rates. However, there are also marketing pundits who disagree. The argument continues and the jury has yet to render a judgment. Still, businesses like to use emojis and even have emoji software to enable customers to express themselves well when leaving feedback. On that note,  consider the following statistics about emojis in subject lines.

• Emails with emojis in their subject lines have a 39% open rate on average. (Klaviyo, 2019)
• Another survey shows that emojis in subject lines increase the effectiveness of marketing by 70%. (OptinMonster, 2020)
• From 2015 to 2016, emails using emojis in the subject line field had open rates of up to 775%. (MediaPost)
• Companies that use emojis in subject lines have 56% higher open rates compared to businesses that do not. (OptinMonster, 2020)
• Businesses should only use one emoji at a time. (Mailchimp, 2021)

Take inspiration from these subject line examples featuring emojis:

• ☁️ Up until June 19th: Try a pair of Ons for 30 days. – On (Campaign Monitor, 2019)
• Meet Alto 👧 and our new Personal Theme Bundle 🔥 – Alto (Campaign Monitor, 2019)
• Say it with our Emoji Gift Notes! 🙈🙉🙊 – Doughbies (Campaign Monitor, 2019)

Email Open Rate by Length of Subject Line

Another bone of contention with subject lines is their length. It has been said that the shorter the better since most people check emails on devices with small screens. Still, there are others that maintain long subject lines that can work, too.

• 40 characters are the recommended length for subject lines. This makes it readable even on smartphones. (Tidio, 2020)
• Mailchimp suggests subject lines to have anywhere between 9 to 60 characters. (Mailchimp, 2021)
• 21- to 25-word subject lines only have a 9% open rate. (Invesp, 2021)
• Emails with 6 to 10 words in their subject lines have the highest open rate at 21%. (Invesp, 2021)
• This is followed by subject lines that have up to 5 words in them. (Invesp, 2021)

Cart Abandonment Emails Subject Lines Statistics

Around the world, the cost of shopping cart abandonment is $4.6 trillion per year. Because of this, it is imperative for businesses to convince on-the-fence shoppers to complete the checkout process. In that case, they need to be creative in contacting buyers who abandoned their carts. In particular, when it comes to email subject lines for cart abandonment reminders.

• Only 45% of abandoned cart emails are opened. (Moosend, 2020)
• 10.7% of cart abandonment emails lead to recovery. (Annex Cloud, 2020)
• Email subject lines that remind shoppers about items they still have not purchased have a 48% open rate. (Klaviyo, 2019)
• That open rate is 4% higher than the average. (Klaviyo, 2019)
• Emails that make shoppers remember they left something behind have a high revenue output per recipient at $11.21. (Klaviyo, 2019)
• 26% of subject lines with personalization have a higher chance of being opened. (Tidio, 2020)
• Shopping cart abandonment emails with effective subject lines have 43.33% open rates. (Barilliance, 2021)
• Exclamation points are attention catchers. Because of this, 29% of marketers like to use it in their subject lines for abandoned cart emails. (Retainful, 2019)

Finding the Right Subject Line

Crafting the right subject line can be a mind-boggling task even for the most seasoned email marketer. For some, it can be tempting to enlist the aid of an email subject line generator. Well, there is nothing wrong with that—you can use the generated lines outright or tweak them to better serve your marketing needs. If you would rather come up with your own, you can use insights from the email subject line statistics above as a guide.

You can augment that with valuable information from email marketing statistics. Data from these can further inform your future email marketing strategies. Moreover, they can help you understand the current state of email marketing as well as of the email marketing solutions industry.

References:

1. Kovalenko, O. (2020, November 10). 50+ great abandoned cart email subject lines examples [with templates]. Tidio. 
2. Saleh, K. (2021, April 11). Email subject lines – Statistics and trends. Invesp. 
3. Oullette, C. (2020, April 23). Email subject line statistics to help you maximize your open rates. OptinMonster. 
4. Serrano, S. (2021, February 23). Abandoned email subject lines: Definitive guide (Updated 2021). Barilliance. 
5. MacDonald, S. (2021, March 24). Email open rates: A scientific, step by step guide for 2021. SuperOffice. 
6. Blanchard, G. (2021). Q: Should you capitalize email subject lines? Or should they read like sentences? Inntopia. 
7. Campaign Monitor. (2019, February 18). How to determine the best length for your email subject lines. Campaign Monitor. 
8. Burnett, J. (2020, April 3). What not to do when writing email subject lines. Ladders. 
9. Allen, O. (2019, November 4). 19 tips to write catchy email subject lines [+ examples]. HubSpot. 
10. Richter, F. (2019, February 26). Infographic: ‘Urgent invoice’ – How to spot malicious emails. Statista.
11. Armstrong, M. (2020, March 31). Infographic: The countries targeted most by malicious coronavirus spam. Statista.
12. Adobe, & Advani. (2020, May). Adobe personalization 2020 Survey​ of consumers and marketers. Adobe. 
13. Matthews, K. (2019, April 3). 13 email marketing statistics that are shaping 2019 and beyond. Convince & Convert. 
14. Korczynska, E. (2019, December 11). Newsletter open rate statistics for 18 industries – what is a good open rate for your industry and how to improve it? Get a Newsletter. 
15. Dean, B. (2021, January 28). 57 key email marketing stats for 2021. Backlinko. 
16. Newsletter2Go. (2018, May 21). Più di 150 oggetti per le tue newsletter. Newsletter2Go. 
17. Klaviyo. (2019, November 19). Abandoned cart benchmark report. Klaviyo. 
18. Kirkpatrick, D. (2017, September 12). Study: Personalized email subject lines increase open rates by 50%. Marketing Dive. 
19. Nelson, J. (2016, March 28). Emoji marketing on the rise. MediaPost. 
20. Cordier, N. (2017, November 16). 5 interactive content myths that are holding your content strategy back. Jeff Bullas’s Blog. 
21. Mailchimp. (2021). Best practices for email subject lines. Mailchimp. 
22. Campaign Monitor. (2019). Using emoji & symbols in your email subject lines (2019). Campaign Monitor. 
23. Moosend Team. (2021, March 2). Cart abandonment stats: Tackling shopping cart abandonment in 2021. Moosend. 
24. Miller, G. (2021). 31 shopping cart abandonment statistics for 2021. Annex Cloud. 
25. Klaviyo. (2019, November 19). Abandoned cart benchmark report. Klaviyo.
26. Thomas, S. (2019, May 30). 13 best subject lines for abandoned cart email campaigns. Retainful. 
27. Agari. (2019, April). Q2 2019: Email fraud and identity deception trends. Agari.
28. Leitch, C. (2021, March 8). The 7 best email subject lines for your job application. CareerAddict.

By Jenny Chang

Jenny Chang is a senior writer specializing in SaaS and B2B software solutions. Her decision to focus on these two industries was spurred by their explosive growth in the last decade, much of it she attributes to the emergence of disruptive technologies and the quick adoption by businesses that were quick to recognize their values to their organizations. She has covered all the major developments in SaaS and B2B software solutions, from the introduction of massive ERPs to small business platforms to help startups on their way to success.