Want to improve your email open rates?
To help, we’ve put together a list of 80 professional subject line formulas with examples — categorized into the five most common emails we all send.
Sumo’s best email subject lines
After sending billions of emails to our customers and subscribers at Sumo, here are 10 of the best performing email subject lines we’ve uncovered:
|1. I was right – and that’s not good for you||69%|
|2. 13 email marketing trends you must know||64%|
|3. Before you write another blog post, read this||61%|
|4. Are we still on for 12?||61%|
|5. You don’t want FOMO do you?||60%|
|6. We’re starting in 5 HOURS||59%|
|7. Missed you, how’s Thursday?||59%|
|8. How 35 influencers grew their sites from 0-10K visitors||57%|
|9. It’s time to rethink Black Friday||57%|
|10. How to Google-proof your mobile site in 2017||53%|
These subject lines are the best of the best. But you’re going to need more than 10 killer subject lines to take your email marketing to the next level.
Part one: content promotion email subject lines
You’ve spent hours crafting an EPIC piece of content, now you want people to read it. One of the best ways to drive traffic directly to your latest piece of content is your mailing list.
For example, Sumo’s email list is the #1 referrer to their new content — driving over 22,000 visits per month.
So if you’re not using your mailing list to promote your new content, you’re missing out on a ton of traffic.
Here are 23 subject line formulas you can use in your content promotion emails:
1. The new email
Formula: NEW: [Blog Post Title]
Groove HQ uses this little trick well to make opening emails about their latest blog posts more desirable:
2. The lessons email
Formula: [Number] Lessons [I/We] Learned by [Action You Took]
Example: 7 Lessons I Learned Doubling Sumo’s Blog Traffic From 100,000 To 200,000 Visitors In One Month
3. The how they done it email
Formula: How [Type Of Person] did [Action They Took]
This formula and example lead to one of Sumo’s best-performing emails with an open rate of 57%.
4. The best-of email
Formula: The Best Of [Topic]
Example: The best time to send emails
5. The you vs. the world email
Formula: How Your [Data Point] compares to everyone else’s
Example: How your email opt-in rate compares to everyone else’s
Check out a variation of this subject line formula, with first name personalization below:
6. The here’s why we email
Formula: Here’s Why We [Something Remarkable]
Example: Here’s why we just spent $1.5 million
Sumo used this headline and received an INCREDIBLE 46% open rate when we announced our name change from SumoMe to Sumo.
7. The my big mistake email
Formula: My Big [Topic] Mistake
Example: My big email popup mistake
8. The authority figure email
Formula: [Authority’s Name] [Topic + Secret/Tips]
Here’s The Authority Figure email in action:
9. The results email
Formula: How We [Result] In [Timeframe]
Check out this subject line being used by Drift below:
10. The urgency email
Formula: [Action] Now
Example: Open this right now
Check out a variation of this email from the UFC below:
11. The case study email
Formula: [Case Study] [Result of Case Study]
12. The how-to email
Formula: How To [Achieve Desired Result]
13. The school of email
Formula: [Celebrity] School Of [Topic]
Example: Tony Robbins School Of Marketing
14. The do this email
Formula: Do THIS [Benefit]
15. The branded newsletter email
Formula: [Name of Newsletter] [Issue #]
Example: The Sumo Email Marketing Newsletter #24
16. The roundup email
Formula: [Number] experts [Topic]
Example: 10 experts share their one EPIC roundup post
17. The avoid these email
Formula: Avoid These [Number] [Topic] [Pitfalls/Mistakes]
You can see this subject line in action from Houzz:
18. The three-pointer email
Formula: [Topic 1], [Topic 2], and [Main Topic]
Example: UFC, sore thumbs, and power words
This formula is used by Tim Ferriss when he’s promoting his latest podcast episodes and blog posts:
19. The art of email
Formula: The Art Of [Topic]
Example: The art of headline writing
Hiten Shah used this subject line for his Product Habits email:
20. The % rule email
Formula: The [Percentage] Rule Of [Topic]
21. The most interesting email
Formula: The most interesting [Person] in the world
Here’s an example from Tim Ferriss:
22. The can’t believe how much you’ll love this email
Formula: Can’t believe how much you’ll love this [product]
Example: Can’t believe how much you’ll love this List Builder app
23. The normally we email
Formula: Normally We [Do Something]. You Get It [New Way]
Part two: sales email subject lines
If someone is on your mailing list, there’s a very good chance they’re interested in what you’re selling. But turning your subscribers into paying customers is a tough trick for any marketer to master.
And before anyone parts with their hard-earned money, you first have to have a subject line worthy of opening.
Here are 18 subject line formulas you can use in your sales emails:
24. The last call email
Formula: Last call: [Name Of Product] closes in [#] hours
Example: Last call: Sumo Pro Account closes in 3 hours
Blinkist uses a variation of this formula to offer discounts to users on their mailing list:
25. The problem solver email
Formula: Fix Your [Problem] Now
Example: Fix Your Email Open Rates Now
If your product directly solves a problem for your audience (which it should), use this formula to grab their attention and entice them to open the email.
Here’s an example of this subject line from Onnit:
26. The try out email
Formula: Try Out [Product] For Yourself
Example: Try out Sumo for yourself
British burger restaurant Byron Burger used a variation of this subject line to promote one of their new recipes:
27. The flash sale email
Formula: [Flash Sale] [Name of Product] [Discount]
Tribe used a variation of this subject line to promote a recent sale:
28. The limited-time sale email
Formula: [Time Left]: [What’s on offer] for [Discount]
Example: 48 hours left: 1 year of Beacon Unlimited for free
Scarcity can boost open rates (and sales) massively. If there’s a time limit on the offer you’re emailing about or limited availability, tell your reader directly in the subject line.
We used the example subject line above to promote our Beacon partnership and it resulted in a 53% open rate.
29. The quick announcement email
Formula: Quick Announcement: [Topic] is here
30. The call out email
Formula: [Audience] [Topic]
Use this email subject line to speak directly to your audience and show them exactly how your product will benefit them.
31. The social proof email
Formula: Proof That [Product] Works
32. The don’t buy this email
Formula: Don’t buy [Product Name] until you read this
33. The versus email
Formula: [Subject] vs [Subject]
Example: $$$ vs % off discount
34. The death of email
Formula: The Death Of [Topic]
Example: The death of Facebook ads
35. The question email
Formula: How can you [Topic]?
Brian Dean quite often uses questions in his email subject lines:
36. The “you” email
Formula: You, A [Desired Result]?
Example: You, an ecommerce all-star?
37. THE IMAGINE RESULT EMAIL
Formula: Imagine [Desired Result]
Here’s an example of this subject line from the Natural Resources Defense Council (NRDC):
38. The seasonal discount email
Formula: Save [Discount] [Items] This [Season]!
Example: Save 25% on shoes this spring!
39. The “you aren’t using” email
Formula: The most surprising [Product] features you aren’t using
40. The can’t be wrong email
Formula: [Number] People Can’t Be Wrong
Example: 5,000 people can’t be wrong
41. The use this email
Formula: Use This [Thing]
Example: Use these WordPress plugins
Part three: cold email subject lines
If you’re running a business, you’ll have to send cold emails. That’s just a fact.
For example, you might:
- Reach out to prospects to pitch your business.
- Want to interview well-known influencers for your blog.
- Meet industry VIPs and learn from the best.
No matter what you’re trying to achieve, and how great your finely tuned email copy may be, you’ll fail if the recipient doesn’t open your email.
Here are 18 formulas you can use for cold email subject lines:
42. The I found you through email
Formula: I Found You Through [Contact First Name] [Contact Last Name]
Example: I Found You Through Mark Zuckerberg
43. The better way email
Formula: A better way to [achieve goal]
Here’s an example of the Better Way subject line:
44. The real reason email
Formula: The Real Reason [Target Market] [Attracted To Product/Topic]
Example: The real reason Shopify store owners use Sumo
45. The truth email
Formula: The Truth About [Topic/Person]
Onnit used this subject line formula in a recent campaign:
46. The problem email
Formula: The Problem With [Insert Problem]
47. The specific event email
Formula: [Event Name] [Reason for Messaging]
Example: SumoCon 2020 Tickets
48. The let me…email
Formula: Let me [action]
49. The right person email
Formula: [Name], are you the correct contact?
Example: Bob, are you the correct contact?
50. The can I help email
Formula: Can I Help with [Topic/Problem]?
51. The idea email
Formula: Idea to help solve [Problem]
Example: Idea to help get people referring friends to your business
52. The meet this new thing email
Formula: [Name], meet [your new product/feature]
Example: Dean, meet FAM!
53. The content share email
Formula: [Name], just wanted to share this [content] with you
Example: Ash, just wanted to share this video on lowering cart abandons with you
54. The your goal email
Formula: Will you reach your [Goal]
55. The found you on email
Formula: Found you on [network/website]
Example: Found you on Twitter
56. The helper email
Formula: [Topic] got you [emotion]? Can I help?
57. The greeting email
Formula: [Time of day], [Name]
Example: Afternoon, Ash
58. The you rocks email
Formula: [Company/name] rocks!
Examples: Sumo’s blog rocks!
59. The chat email
Formula: [Name], I’d love to chat about [topic]
Part four: follow-up email subject lines
Whether you’re emailing someone you just met or trying to get a response from a cold email, following up is incredibly important.
80% of non-routine sales occur only after at least five follow-ups. And 44% of salespeople give up after one attempt. If you’re not following up, you’re missing out on huge opportunities to grow your business.[*]
Here are 14 formulas you can use for follow-up email subject lines:
60. The we discussed email
Formula: Here’s the [topic] we discussed
Example: Here’s the quote we discussed
61. The thanks for your time email
Formula: [Name], thanks for your time [today, yesterday, last week]
Example: Chris, thanks for your time today
62. The we still on email
Formula: We still on for [Date/Time]?
Example: We still on for Tuesday?
Here’s a super smart variation of this email from Virgin Atlantic to follow up with people who searched for flights on their website:
63. The ways to get started email
Formula: [X] Ways to [Experience Growth] with [Product]
Example: 5 Ways to Kill Your Next Workout With Sumo Protein
64. The I forgot email
Formula: I forgot to mention [Topic]
65. The we haven’t email
Formula: We haven’t [Action]
66. The missed you email
Formula: Missed you, how’s [Day]?
Example: Missed you, how’s Thursday?
67. The to-the-point question email
Formula: What’s your [Question]
Example: What’s your calendar look like next Wed at 3 pm?
Justin Jackson used this subject line in a message to his email list:
68. The follow-up “re:” email
Formula: Follow Up re: [Topic discussed]
Example: Follow Up re: Mobile popup strategy
69. The awesome to meet you email
Formula: Awesome to Meet You at [Event/Place] [Date/Time]
Example: Awesome to Meet You at SumoCon Last Week
70. The touching base email
Formula: Touching Base Regarding [Topic] [Date/Time]
Example: Touching Base Regarding Our Pitch Yesterday
71. The quick check-in email
Formula: Checking in on [topic]
72. The Steve Jobs email
Formula: [One more thing] about [topic]
73. The something bad happened email
Formula: Hey, I [something bad that gets attention]
Examples: Hey, I messed up.
Part five: transactional email subject lines
Chances are your company sends a ton of transactional emails. They are emails like order confirmations, receipts, and billing reminders.
As these emails are usually triggered by customer actions, like making a purchase or signing up for your product, transactional emails have an open rate of eight times higher than normal emails.[*]
But you still want to do everything in your power to ensure your transactional emails are opened. After all, they often contain important information.
Here are 7 formulas to help you craft amazing transactional email subject lines.
74. The welcome email
Formula: Welcome to [Brand/Name]!
Example: Welcome to Sumo!
Here’s an example welcome email:
75. The let’s get started email
Formula: Welcome to [Brand/Name] – [Action encouraged]
Example: Welcome to Warby Parker! Try on some glasses now
76. The thank you email
Formula: [Business name]: Thank you for being a customer
Example: Dollar Shave Club: Thank you for being a customer
Check out an example thank you email from Medium below:
77. The reminder email
Formula: [Date/Time] You [Action took]
Example: Last Wednesday You Added Nike Running Shoes to your basket
78. The order email
Formula: Your order of [product name]
Example: Your order of Spiderman 3
79. The next steps email
Formula: Welcome to [product name] – [next steps]
Example: Welcome to Uber – here’s how to take your first ride
80. The action required email
Formula: Action Required: [Task]
Example: Action Required: Confirm Your Email Address
Benchmarking your email open rated
Many factors affect average open rates, including how your subscribers joined your email list in the first place, and if you’re sending an email to an extremely segmented part of your list.
Here are the average email open rates across 45 industries:[*]
|Industry||Average Open Rate||Average Click Rate|
|All non-labeled accounts||22.71%||2.91%|
|Agriculture and Food Services||23.31%||2.94%|
|Architecture and Construction||22.51%||2.51%|
|Arts and Artists||26.27%||2.95%|
|Beauty and Personal Care||16.65%||1.92%|
|Business and Finance||21.56%||2.72%|
|Computers and Electronics||19.29%||2.08%|
|Education and Training||23.42%||2.90%|
|Entertainment and Events||20.51%||2.36%|
|Health and Fitness||21.48%||2.69%|
|Home and Garden||21.60%||3.03%|
|Marketing and Advertising||17.38%||2.04%|
|Media and Publishing||22.15%||4.62%|
|Medical, Dental, and Healthcare||21.72%||2.49%|
|Music and Musicians||21.88%||2.94%|
|Photo and Video||23.24%||3.23%|
|Recruitment and Staffing||21.14%||2.53%|
|Restaurant and Venue||20.39%||1.40%|
|Social Networks and Online Communities||21.06%||3.32%|
|Software and Web App||21.29%||2.45%|
|Travel and Transportation||20.44%||2.25%|
Now, you don’t need to take these numbers as gospel. Yours can be lower depending on your situation, but if you can stay in the 15% – 28% range, you can be confident that you’re doing well.
3 bonus tips to improve your email subject lines
You got the email open benchmark, and the above email subject line formulas and examples will no doubt help you to improve your open rates.
But to truly maximize the potential of your emails, you’ll need to do a little experimenting and testing with your subject lines.
Here are three ways to further improve your open rates.
1. Experiment with emojis
A report from Experian (since removed from their site) found that 56% of brands using emojis in their email subject lines saw a higher open rate on their emails.
The below chart from Mailchimp shows the most popular emojis used in subject lines:[*]
2. Test various lengths
For most businesses, there’s no direct coloration between subject line length and open rates. But you should think about where your subscribers are opening their email.
Based on an email marketing stats report by Litmus, the majority of your opens came from mobile devices and tablets.[*]
With smaller screens, you need to ensure your subject line fits within the allocated space. The rule of thumb is to keep your subject line between 30 and 60 characters.
3. Use time-sensitive words
Using time-sensitive words like “urgent” and “important” can result in much higher open rates. Data from Mailchimp (since removed from their site) proves it:
Where applicable, try to weave these words into some of your subject line formulas to inspire action from your subscribers.
- Important: 21 Lessons I Learned by Exercising Every Morning
- Sale Alert: 20% Off Sumo Pro
- Breaking: Warren Buffet’s investing secret
We all know the story of the boy who cried wolf and because not every email you send will need immediate action from the reader, it can be best to use this tip sparingly.
This means that when you do include time-sensitive words in your subject line, your readers know they MUST act.