Writing a Subject Line

For such a small thing, writing a subject line can be deceptively difficult. As it’s the very first part of your email any recipients will see, it’ll be one of the (though probably not THE) primary drivers in whether or not they actually open it.  

There really isn’t much need for a technical guide covering how you create a subject. Nothing more to that than clicking in the subject field and typing. The hard part is writing something that does your email justice while convincing potential readers to open it.

How can you do that?


Keep It Short
The space allotted to subject lines in an email inbox is not infinite. There’s a pretty limited amount of room for you to convey “Please open my email, thank you!” and you want to make sure everyone sees the entirety, or at least the important parts, of anything you write.

How short, exactly?

Eight to Fifteen words. Or somewhere around 50 characters.

It’s important to think of the myriad ways a subscriber might receive your email: it could be at their computer, it could be on a tablet, or it could be on their phone.

It may or may not surprise you to learn that around 50% of all email is read on a phone (and most of these opens occur on iPhones), with another 35% on computers, and the remaining 15% on tablets (as with phones, most tablet opens occur on Apple’s iPads).

Phone screens? They’re small. So you don’t have a lot of room to write a subject that will fit within the width of a phone’s screen.

Do you have to keep the subject this short? No, you don’t. But if it’s important to you that a recipient be able to read the entire thing, short is the only way to go.

Keep It Simple, Snappy, and Interesting
Spur someone to open your email. Give them a reason. We are all inundated with email messages from pretty much every business we’ve ever been anywhere near, so it’s important to stand out from this often overwhelming crowd.

How can you stand out? You and/or your business have a personality of some kind. Use it.

You can also add emoji to your subject line for some fun visual appeal - click the smiley face icon to the right of the subject field to add them, just like on your phone. You may also want to customize the preview text for your email. This text is what they will see after the subject line before opening the message in their mail app, so it's a good chance to entice recipients to open and read the entire email.

Don’t Be Spammy
Nefarious entities who spend all day spamming people have mastered the art of pestering. Don’t be like them. Don’t sound like them. We could list a near infinite list of spammy subject lines, but opening up your spam folder and looking over the first ten subject lines you see there works just as well.  

How about examples of good subject lines?

Thanks for being you. We got you a gift!
Photojojo.com in an email that included a $10-off-any-order promotion.

Take a break for cool gear!
Borrow Lenses, asking that we take some time to read their email about their cool photo equipment.

Small gifts have a big impact!
The San Francisco Film Society, soliciting donations.

Big Ideas + Brief Moments
Filmsupply, describing the videos that were being shown off in the email.

Cats. Comets. Laughs. Seconds. How do you measure the passing of time?
The Exploratorium, advertising their new app.

If you really want to get a good idea of how to write a successful email, take a look at the email in your own inbox. Which emails resonate with you? Which ones do you delete without reading? Always keep this in mind when designing your own emails.


Now that you've picked the perfect Subject Line, it's time for your Sender Information.

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