What I Found When I Compared 153 SaaS Email Subject Lines
Some of the most viewed posts on my site are ones I would put under the category “should and good.”
Comparing Email Cadence Across 5 SaaS Free Trials (14-Days) and How many Emails Does a 30-Day Free Trial Need? compare different onboarding series on a single topic. In the case of the two posts mentioned, I covered the frequency with which different companies sent onboarding emails. I consider these posts to be “should and good” because you can use them as a benchmark for what you “should” be doing or what a “good” number of emails is.
Today I have another “should and good” post focused on subject lines. I knew I wanted to compare at least 100 subject lines from the different onboarding email breakdowns I’ve done, so then I had to decide how to slice and dice the info.
Here’s what I decided:
First, I’ll cover some interesting stats about the subject lines
Then, I’ll pull out some common themes
Finally, I’ll compare subject lines grouped by the type of email they’re associated with
Sound good? Let’s get started.
Stats From 153 SaaS Email Subject Lines
Before categorizing the subject lines, I decided to pull out some general stats. Ya know, get a lay of the land by pulling out some insightful numbers. If you want to review all 153 subject lines yourself, you can download my spreadsheet with all the subject lines + stats + insights by entering your email below.
How long should SaaS email subject lines be?
The length of a subject line isn’t really something I consider until after I’ve written a few options. After I’ve chosen one, I run it through an email subject line checker to make sure it’s generally a good length.
Even though I don’t give much thought to email subject line lengths, I still thought it a useful stat to bring forward.
For the 153 subject lines I analyzed, the average character count was 36.
Not sure what that looks like? Here are a few example subject lines with 36 characters:
It’s Time to Make Your First Invoice
Steph, the Best Decisions Start Here
Finish your survey fast — here’s how
There was a tie for the longest subject line of the batch, both with 66 characters.
One came from Shopify: How to drive traffic to Double Cat Studio (without paying for ads
While the other was from Monday: Hey Stephanie — build your first board, and get your team started!
Monday is not afraid of variety since they also had the shortest subject line with the three-character long “fyi.”
Sentence case vs. title case
Another tiny subject line detail that I know I’ve googled before is sentence case versus title case. For a refresher, a subject line using “sentence case” would only capitalize the first word, and then any proper nouns. Title case, on the other hand, capitalizes nearly every word.
71% of subject lines used sentence case, making it the most popular with SaaS companies.
Examples of sentence case subject lines include:
Build your list with a little help from us
Please confirm your email address
Title case is fairly common with 22% of the subject lines using this style.
Examples of title case subject lines include:
Upgrade to Grammarly Premium, Become a Stronger Writer
Activate Your Mailchimp Account
Want to really stand out? Be among the 7% of subject lines using only lower case.
Have you ever seen an all-lowercase subject line out in the wild? A few from my list include “join us for a webinar?” and “the end is coming,” both from Monday. A few other companies used lowercase at times, but this style is definitely in the minority.
At the end of the day, the best capitalization choice is one that matches your brand tone and identity. Title case is more traditional and formal, while sentence case is casual and friendly (like a message to a friend). If your brand is very relaxed and unique, then a lower case style may work best for you.
To emoji or not emoji
The final subject line choice I set out to quantify was to emoji or not emoji.
Across 153 SaaS onboarding emails, only 12 used emojis.
These 12 include lines such as:
Grow your business in 2019 with the help of video 💪
✅ What do you need to work on?”
Based on entirely anecdotal evidence within my inbox, emojis seem much more common in subject lines for retailers as opposed to software companies.
The more popular subject line addition was punctuation at the end, with 30% using it.
Exclamation points (Your first survey response!), question marks (Too busy to add your team?), and even a few periods (See who did what, when.) all added to the tone of the subject line.
Common SaaS Email Subject Line Styles
After sorting through the nitty-gritty details of the subject lines, I went to work finding recurring themes. While there are a ton of ways you could divide the subject, I chose 8 subject line types to highlight.
Social proof
Social proof is always powerful to include, but I think it’s even more impactful in onboarding emails. All 153 subject lines analyzed were sent during a free trial, so it makes sense that they’re still trying to sell me on the dream.
Examples of SaaS subject lines using social proof include:
Jake's Thriving. You Can Too.
9 out of 10 customers say Gusto is easier than their old payroll
Join the millions taking control of their money
How-to
Another subject line structure that popped up a few times was the “how to.” These often came attached to emails talking about specific product features, and followed a structure of “how to achieve X desirable result.” Examples include:
How to collect your profits
How to drive traffic to Double Cat Studio (without paying for ads)
A few other “how” subject lines didn’t follow that pattern, such as “How do you eat an elephant? 🐘” and “time is finite (how are you gonna spend yours?).”
Using the recipient’s name
My name showed up a TON in the onboarding email subject lines. If you count references to my “business name” (which is just my LLC), there are 17 mentions of me in the 153 subject lines. That’s more times then emojis were used. My name was used in subject lines such as:
Steph, your Zendesk Trial
Please confirm your email, Steph
Life is a series of missed opportunities, Stephanie
Does seeing your name in a subject line make it stand out to you? And does it feel personalized? Let me know down below. Personally, the verdict is out. It’s common, for sure, but I’d love to know how effective it is these days.
Question
As mentioned earlier, punctuation was relatively common across the subject lines analyzed. Of the lines with punctuation, a majority of them were questions. Subject lines entirely or partly questions accounted for 18+ of the 153. Examples include:
Need logo help?
Have You Seen the Difference FreshBooks Makes?
How long does it take to integrate?
Straightforward
Look, I love witty subject lines. But there’s a time and a place for them. I was happy to find a handful of simple, straightforward subject lines in the batch. Most often, these are attributed to welcome emails or end of trial reminders/CTA emails. No-frills examples include:
Your trial ends soon!
Verify your email address
Hey there. Welcome to Wistia!
Outcome-focused
Another subject line type I was happy to see were lines focused on outcomes. After all, tools are just a means to an end, and it’s the end result that people actually care about. Outcome focused subject lines typically accompanies “Feature Spotlight” emails. Rather than wrongly focusing on the details of what the feature is, these SaaS companies highlighted what they can help a person achieve. Way to go! Want outcome-focused examples? Here ya go:
Want to Get Paid Lickety-Split?
Grow your audience with Facebook and Instagram Ads
Add your team, enjoy less paperwork
The subject lines can mention the outcome alone or follow a formula along the lines of “Achieve X result with Y action.”
Action-based
In addition to outcome-focused subject lines, I spotted a handful of action-based ones as well. These subject lines are clear and directive, such as:
It’s Time to Make Your First Invoice
Send a personalized birthday email to your subscribers
Time to add your employees to Gusto
Interestingly, a few added the element of “time” to the action. I think this is a smart way to add some urgency to an email without using false time-scarcity tactics.
“Pro”
I was expecting to find curiosity-driving questions, reassuring social proof, and to-the-point descriptive subject lines, but I wasn’t prepared for this final theme. A few separate companies all used the “pro” or “expert” angle. Examples include:
Write Like a Pro. Here’s 40% Off Grammarly Premium!
Host Like a Pro
💡 Becoming an expert
In a way, these emails are outcome-based. I found this sub-category too unique to lump under the outcome category since it isn’t your standard business outcome. It’s a much more abstract and personal outcome, but I’m here for it.
Onboarding Subject Lines by Email Type
If you’ve ever seen one of my breakdowns, you’ll see that I aim to categorize emails. It makes it easier to compare email types across series and think about planning your own series from a high level.
So naturally, I grouped the 153 emails by their email type. While examples for the recurring themes in the previous section were from different types of emails, in this part, we’ll look at variety within the same type.
Welcome
It’s best to use your company name in the welcome email, and all the subject lines below got that memo. When it comes to welcome subject lines, keep it simple like these:
Stephanie, say hello to Double Cat Studio
Welcome to Salesforce CRM. Start with the basics.
⭐ Welcome to Pipefy!
Steph, let’s get started with Customer.io
Building Block
“Building Block” emails are the messages that call attention to THE feature you don’t want a new user to miss. This could be the one that gets them closer to their goal, is required before they do anything else, or simply the feature they’ll use over and over. Some building block subject lines mention the feature by name, and others are a bit vaguer and ~alluring~. Check out these examples:
It’s Time to Make Your First Invoice
What is a note?
You’re Missing the Best Part of Grammarly
Steph, the Best Decisions Start Here
Feature Spotlight
After a new user has taken advantage of the building block feature, you can introduce some other helpful steps. The “feature spotlight” category showed up the most in this analysis, with 33 subject line examples in total. Just like the building block emails, sometimes these subject lines are straightforward, and sometimes they’re clever:
How to connect with millions of shoppers
Are you reaching your customers on the right channels?
The many ways to search in Evernote
FREE social automation (yep, i’m serious)
Use Case
Use cases combine a few features or tools to show off how you can accomplish a goal. For example, Salesforce lets you know you can “make it rain.” Most use case subject lines are going to be outcome-focused or talk about a desirable result. Just like these:
Make it rain with Salesforce.
Wait, I didn’t spend $300 at the taco truck…
Budgeting doesn’t have to hurt
Don’t Zoom Alone
Case Study
Case studies are success stories. These are the subject lines to flaunt what you’ve got! Use social proof and amp people up about the possibilities if they stick with you. Use these as inspiration:
We know you’re curious…
Jake's Thriving. You Can Too.
This startup CEO is a one-person video team 📹
Grow your business in 2019 with the help of video 💪
Value Add Content
I love value add content emails. Rather than spending the whole free trial talking about your product and encouraging people to use it, just send some free knowledge. Pass along guides, courses, webinars, and articles. Teach users and you become a valuable resource. Here are how a few SaaS companies share their content via email:
Steph Knapp 5 year customer support strategy
Join a live training
Introducing Dropshipping 101: Free dropshipping training
Tips for achieving video advertising success 🙌
Support
A few of the onboarding email series that I’ve written breakdowns for include support emails that are more person-to-person and plain text. These emails connect users to customer success agents or point out where a person can get help. Not surprisingly, there’s a theme of having a supportive or collaborative tone:
Working together on your Customer.io trial
I’ve got your back
Steph Knapp <> Pipefy
Payroll with Gusto!
Offer
Sometimes software companies choose to sweeten the deal a little bit. Offer emails tend to come towards the end of the onboarding series and offer a discount if you upgrade. Typically the discount applies if you choose a larger plan, such as an annual agreement over monthly. Sometimes the exact deal is in the subject line, and sometimes it isn’t:
Same Great Features, Even Better Price
Get 40% Off Any Individual Plan + Land Your Next Gig With Style
There’s more Salesforce to love when you customize and extend.
50% OFF Annual Plans. Love your writing this year. 💗
CTA
When you’re down to the wire, there’s no time to be cute. It’s always a good idea to give users a heads up when their trial is close to ending, and it’s good to be clear about it. The CTA subject lines are typically straightforward:
Important: Your trial expires in 4 days
Your trial ends soon!
your trial ends today
Give me a call about your free trial
Winback
A free trial has come and gone. What’s a company to do? You can ask nicely, offer a discount, or just play the emotion card. Winback subject lines can be more emotional than any other email type:
We miss you already
I want you back for good
This Offer Goes *Poof* in 2 Days
Want your free trial extended?
What now?
You’ve just taken in a ton of SaaS email subject line insights and ideas—now what? Here’s where you can go from here:
Get access to all 153 subject lines. You can download my spreadsheet with all the subject lines, stats, and themes. Plus links to all of the onboarding email breakdowns I pulled them from by filling out the form below.
Explore top-notch email copywriting examples. You’ve seen subject lines, now look inside emails with these awesome copywriting examples.
Create your own SaaS emails with 30+ templates. My free Essential SaaS Email Series Templates will get you started on five important email sequences.
I compared 153 SaaS email subject lines to find common themes, best practices, and style choices.