(subject lines) how to get better email open rates

Tip #1 – all lowercase

Go check your inbox again. How many are using all lowercase for their subject line?

Probably none.

I almost always use lowercase:

Friends write to friends in lowercase. You want your subscribers to treat you as their friend. Writing in lowercase kind of implies that you’re friendly, informal, and are open to chillin.


Tip #2 – Broken English

Occasionally, I’d purposefully write broken English to capture people’s attention. So that I stand out from the crowd and hopefully people remember me better than the other guys in their inbox.

Another example:

Tip #3 – Curiosity

We humans are social creatures. Don’t tell me you don’t want to know what’s happening with your family, friends, colleagues, partners?  We’re always curious about other people, sometimes to the point of being nosy.

Here are some examples of curiosity-driven subject lines I’ve used:

  • Weird culture in my country?
  • Don’t write another email until…
  • New subscribers not opening your email?
  • This person spammed me

Weird culture in my country? I wonder what that is.

Don’t write another email until… Hmmm until what? I need to know about this before writing my next email.

New subscribers not opening your email? I definitely got to find out why so that I can avoid this problem.

There was this one time I accidentally sent an email with not only the default subject line of [Subject line here], but also the default content:

As you can imagine, people were curious, they opened the email and replied me with messages like these:

Tip #4 – Short

Short subject lines catch your attention because they’re easier to scan (people scan, they don’t read).

Plus they just stand out from other emails because most have longer subject lines.

Don’t believe it? Go check your inbox 🥱

If you do what most people do, you don’t stand out.

Also, when viewing your email inbox on a mobile device, as nearly 1.7 billion people do around the world, long subject lines are going to get cut off.

Some examples of short subject lines I’ve used when sending to creators and small businesses:

  • are you making this mistake
  • get attention in 2 steps
  • help
click for larger image


Tip #5 – Demonstrate value immediately

Include benefits in the subject line (i.e. what’s in it for them).

But first you must understand that benefit is not the same as feature.


  • Send sequence/drip emails
  • Send broadcast emails
  • Collect email addresses using our forms


  • Sequence emails enable you to automatically follow up and build relationships with your subscribers, even when you’re sleeping
  • Broadcast emails is useful when you have a new offer or newsletter or blog post that you want subscribers to know
  • No more manually copy-pasting emails from Sheets/Excel to our system. Let our forms do the hard work and collect leads automatically for you, even when you’re on vacation

Features (computer):

  • 16 GB RAM


  • Fast loading and zero lag — open every app and your computer will still be running blazingly fast. No more waiting. No more frustrations.

Another e.g. from WebEngage:

Combine short subject line + benefit and you’ll get more email opens.

E.g. Subject: How to get more email opens

This is short and contains benefits (everyone wants to know how to get more email opens).


Tip #6 – Contrast

By contrasting/contradicting in a single subject line, people naturally want to open your emails because it doesn’t make sense. They want to find out what it’s all about (again, curiosity).

Sometimes when you use 1 hack, it creates/results in another hack.

In this case, contrast creates curiosity.

E.g. of contrast subject lines:

  • I’m coming back for poor food
    • (normally you’d never come back if the food is poor)
  • Overweight beauty expert helps moms lose at least 20% of their weight
    • (hmm… why is a beauty expert overweight? I’ve got to check this out)
  • The man with the woman voice
    • (how come? What happened to him [or her]?)
  • How this Karate beginner became champion
    • (how is it possible that a beginner becomes the champion?)


Tip #7 – Mini Skirt

What’s the likelihood that this guy drops off the cliff and dies?

50 – 50?

What if a girl wearing a mini skirt walks up to him while he is still “cliffhanging”?

In your emails, right before you end the email (e.g. in the PS. section), you introduce something that “excites your readers, or something that arouses their curiosity”, but you don’t “complete the whole picture”.

You tease them…

Like how a mini skirt teases guys. Or if you’re a gal, being told you can get the just-released Hermès bag at half-price but they don’t tell you how.

You want to keep the skirt long enough to cover the essential parts, but short enough to make it interesting and exciting.

Because the human mind doesn’t like incompleteness, we’ll be on the edge of our seats, eagerly waiting to finally know what the answer is…

… whether he will drop off from the cliff and die

… or how the inside of that skirt looks like

Hollywood movie trailers are the absolute master at leaving you “hanging”. You’re pushed to the edge of your seats. Suddenly you’re at the theater on release day.


In your PS you could write:

PS. Tomorrow, I’m going to reveal behind the scenes on how I managed to get featured on the front page of Forbes. Make sure to read my email tomorrow.

PS. Open my email tomorrow and I’ll teach you how to come up with an endless supply of story ideas to hook people into your emails.

Or if you’re giving a top 7 steps to achieve a result — you give 4 steps today, and leave the remaining 3 in another email. If they miss any step, it becomes incomplete.

The subject line for your next email then continues where you left off.

E.g subject: miss these 3 steps and you’ll bake a horrible cake


Wrapping Up

Use these subject line tips to get more email opens:

  1. all lower case
  2. Broken english
  3. Curiosity
  4. Short
  5. Benefits
  6. Contrast
  7. Mini skirt

Your brain might already be buzzing around with ideas.

My suggestion is to apply the subject line tips ONE EMAIL AT A TIME.

Pick 1 tip from above, write and send your subject line. After that, pick another. Don’t FOMO.

Learn and apply ONE AT A TIME. Improve ONE EMAIL AT A TIME.



Use each of these hacks sparingly. Mix and match them. Don’t always use the same hack — e.g.  you keep using the curiosity hack successively for 5 emails.

As with anything, anything that gets repeated over and over again becomes predictable. And predictable is boring. 

Boring = no emails opened.


If you want to increase email opens w/o playing with subject lines, go here.

Special thanks to WebEngage for the umbrella image.

About the Author

👋 My customers (Content Creators) send 30M emails/month via BirdSend. They save 80% in email tool expenses every month while still enjoying high email opens.

Welly Mulia

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