Got an email newsletter coming up?
If so, you’ll know that the subject line you choose will have a large impact on the number of recipients who will open, read and click your email.
And with this in mind, I thought I’d share the results from a recent experiment – and my findings might change the way you think about the subject line in your next email campaign.
My email subject line experiment
Over the last 8 months, I’ve sent 35 email campaigns to an average of 280 people (not a big list I know, but I’m working on it!)
These 35 emails have had subject lines which can be grouped into 2 main categories:
- Positive email subject lines
- Negative email subject lines
Here’s a bit more detail…
Positive email subject lines
26 of the subject lines focused on sharing knowledge or learning something new, for example:
- How to become a Facebook Ninja
- Copywriting checklist: How to turn prospects into customers
- 4 Facebook update ideas for your business
Negative email subject lines
And just 9 (25%) of the subject lines focused on avoiding pain, causing controversy, or they simply suggested what NOT to do, for example:
- Email newsletters: Avoid this mistake
- Social media: 4 things to stop doing in 2015
- Blog writing: Avoid the trap of writing about your business
The numbers from my experiment may be small (and this may be very unscientific) but I was surprised with what I discovered.
Email campaign clicks by subject line:
The table below shows my best 10 subject lines in terms of email clicks, with the negative email subject lines underlined with red (click to enlarge the image).

As you can see, the best performing email campaigns I’ve sent tend to have used negative subject lines, even though the overwhelming majority (75%) of the emails I’ve actually created and sent have focused on the positive.
In other words, 7 of my 9 negative subject lines made the top 10!
Stop being Likeable?
Writing subject lines stated in the negative feels wrong to me, but it’s clearly what my recipients enjoy most. What about your subscribers? What types or emails are they more likely to open, read and click?
The first (and hardest) step is to start sending regular email newsletters, then you can start crunching the numbers.
ps – wondering if email still works? These 35 email campaigns (sent using simplemail) have generated 1414 clicks through to the likeable blog.
Like this article? You should check out email subject lines: avoid this common mistake