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Writing killer subject lines

Hello Friend,

Last email I asked you what you wanted us all to learn about next. Here’s a little status update

  1. This time: Writing killer subject lines
  2. Next time (all going well): Email open rates (based on analysis of our own data)
  3. Later: Mapping out the emails your app should send

I can’t wait for the Email Open Rates newsletter. We have a great data scientist working to uncover gems of information in our data… But this email is about writing killer subject lines

I used to be bad at writing copy. So bad that at my last job, we hired someone to compensate for my poor skills.

If you’re anything like me, when you’re bad at something you want to get better. About 8 months ago, I learned about a series of Ebooks from CopyHackers. I read them cover to cover. If I’ve gotten better at copywriting, it’s because of these books as well as lots of practice and experimentation.

When you guys said you wanted to learn more about subject lines, I knew I had to speak with Joanna Wiebe, copywriter extraordinaire and founder of

Joanna kindly broke down subject lines into her Top 5 things to think about when writing subject lines. We got a little excited about talking to Joanna and decided to record our conversation. So click on the 3 minute video and if you want to learn subject line kung fu like Neo in the Matrix. Or read on for the text version of Joanna’s wisdom:

Here are Joanna’s 5 things to think about when writing subject lines

  1. The Basics
  2. The Trigger
  3. What’s in it for them
  4. Friend-ness and Relevance
  5. Context

So let’s dig in to what Joanna recommends (note: I’ve paraphrased a few lines, but these great ideas are hers not mine):

1. The Basics

  • Use the brand name somewhere in the line, even if it’s in the From line
  • Stick to 50 characters with spaces – or less (unless you have data that suggests longer headlines work better)
  • Don’t use title case but rather use sentence case
  • Avoid overtly spammy words, or more than 1 spammy word
  • Mirror the subject line in the email headline

2. The Trigger – Why is someone getting the email?

  • Are people expecting this email or aren’t they?
  • How long ago did they ask for this email?

3. What’s in it for them?

  • In a newsletter, what’s intriguing, timely or curious about the subject?
  • If it’s an enticement to upgrade, what’s the offer? When does it end? What new highly desirable feature should I want to get?
  • If this is a “welcome” email, what will make them feel welcomed? Do they event want to feel welcomed, or do they just want access to your free ebook?

4. Friend-ness and Relevance

How can you make the email look like it’s from a trusted source who understands them, not from a company with an agenda? Get strategic about:

  • Personalization
  • Recent behaviors (e.g. “you just signed up”)
  • Time since we last spoke (e.g. “It’s been a while, Sarah”)
  • lowercase, like a friend would write.
  • Tone
  • Avoiding creepiness! How do you know so much about me? If an email gets triggered from inside an app, what level of detail should you share with me in the subject line?—When does it get creepy?

Or, if they consider your brand a friend then use your brand voice. Good examples of this are and Kate Spade

5. Context

Remember, you’re trying to get noticed in the midst of a massive inbox (in many cases) filled with competing messages from invited and uninvited people. You must consider context in all copywriting, and subject lines are no different.

Thanks Joanna Wiebe for chatting with us.

Listen to the audio (15 mins).

Want this newsletter to have more issues with audio and video? Let me know. It’s a little more work, but you guys are worth it.

  • Colin