The Easy Guide To Email Subject Lines (with examples!)

Marketers really like their lingo and abbreviations. KPIs! CTAs! CTRs! IPAs!

(That last one might be something else.)

All this jargon can make some concepts seem complicated when really, they’re pretty easy to understand.

You’re a smart cookie. You just don’t have the time to memorize a gajillion technical terms and read through 14 case studies about what works and what doesn’t.

So.

I’ve put together an easy, mostly jargon-free guide to email subject lines, with some handy examples right from my inbox.

We’re gonna talk about

1. The most important metric for evaluating your subject lines;
2. A few different types of subjects; and
3. Some best practices that you can use for easy tweaking.

Let’s do it.

How do you know if your email subject lines are any good?

It’s commonly said that the only job of the subject line is to get the reader to open the email.

Then, it’s the job of the email’s body copy to get them to click through to the website where the sale (or reservation, or booking a call, or whatever your conversion is) can happen.

With this in mind, it’s natural to think that a high open rate is super important.

Quick definitions: 

Open Rate = Percentage of email recipients who open the email

Click-through Rate = Percentage of email recipients who click on a link in your email

The thing about open rates is…they can be wildly inaccurate.

To track opens, email marketing providers (like MailChimp) include a small invisible image in your email. When the reader opens the email, the image is downloaded from the provider’s server. By tracking those downloads, the email provider can track your email opens.

But this system has flaws. Many readers have their inboxes set up with a “preview panel” that downloads images. So the email could be tracked as opened, even if the user just quickly scrolled by. Or the user could be reading your email as plain text, without any images. In these cases, your email opens aren’t being tracked. 

Even when opens are tracked, they may not be saying what you think they are.

How often do you open an email and then immediately click out of it? You had no intention of reading it. You just wanted to get it out of your unread messages. 

Even worse—an open that results in an unsubscribe still counts as an open. If you have an open rate of 65% (yay!) and an unsubscribe rate of 50% (boo), you have a big problem.

This doesn’t mean that email subject lines don’t matter. They do! 

But instead of focusing on your open rate, your click-through rate is a much more important metric. It’s the money maker. Better to have a modest open rate and a good click-through rate.

This means your subject lines need to attract opens from people who are likely to take the next step—and click through to your website.

Now, let’s talk about some different categories of subject lines that you can experiment with.

6 types of subject lines to try

1. The message to a friend

Look at your inbox right now. It’s pretty easy to spot the marketing messages against the personal ones, right?

Marketing email subject lines tend to sound sales-y and impersonal. But messages from friends and family? They have subject lines like: 

• Pics
• holiday plans
• Hey pretty! What’s your address?
• Hola, ladies.

(These are all real subject lines from my inbox, btw). If you can write your email subject lines to your list like you’re writing to a friend, you build personal rapport and may stand out in a sea of sales emails.

2. The super straightforward subject line

This usually works well when just knowing the contents of the email is enough to get the reader to open and click. Think discounts, limited-time offers, sales, and lead magnet deliveries. 

Here are a few from my inbox: 

• Here’s the link you requested, love!
• Every single thing is 25% off!
• FREE cocktail book inside!?

3. The benefit-focused subject

Why should the reader bother with your email? In other words, what’s in it for them?

Remember why people signed up for your emails in the first place—because they thought they’d get something out of it.

By including a benefit, you answer the “what’s in it for me question.” And people who are looking for these answers are probably also looking for your products or services.

Some examples (with the benefits in bold):

• Achieve results with your words — starting today
• Auto-post to Instagram and save time
• 14 advanced SEO techniques to double your search traffic

4. The curiosity stoker

Sometimes a message pops up in your inbox that makes you stop what you’re doing because you have to know what this is. A subject that stokes your curiosity can be wildly successful in getting people to click. 

But the insides of these emails have to deliver on the promise. If your readers realize that your subjects are just clickbait, they’ll stop opening entirely.

Here are a few that got me to click ASAP: 

• The most important skill in life
• My friend is ??
• Sus Activities and I AM THE DARKNESS 

That last one was actually the title of a post on NextDoor, which became the subject line in their daily digest email. I clicked immediately because…what the heck?

I wasn’t disappointed.

It was a neighbor threatening to go full Liam Neeson on whoever keeps knocking on her door at midnight. She’s my new favorite person in the neighborhood.

5. The shocker

Some marketers like to shock their way into your inbox. They may use curse words, surprising imagery, or controversial opinions to get you to click.

This can work, but if you don’t know your audience really well, it can be off-putting. And since we’re in the hospitality business around here…it’s a dangerous proposition. 

There’s one very talented writer whose emails I read regularly and really enjoy. But his subject lines can be weirdly macho and hyper-sexualized. Here are some actual subjects I’ve received from him:

• Whiskey dick
• On almost getting laid in Belarus
• Tastes like a blow job feels
• Headlines you want to have sex with

Gross, right? You could make the argument that while I don’t like these subjects…I still haven’t unsubscribed and I still read them. So they’re working. But they’re also narrowing his potential audience.

So tread verrrrry carefully if you want to shock people into opening your messages. It could backfire.

6. Combinations

Many email subject lines combine these different techniques to great effect! Curiosity, for example, can work really well with a benefit. I had this one in my inbox, which certainly caught my attention: 

Sales combined with self-care? I don’t even sell courses but I was curious enough about this to check it out.

You can mix and match all these different subject styles to come up with your own high-performing email marketing cocktail. 

Email Subject Line Best Practices

Regardless of what style you choose for your email subject line, here are some guidelines (not rules!) that may help. 

Avoid title case

Email subject lines in title case look like they come from brands. We’re not trying to trick anyone into thinking your email isn’t from a brand, but we do want your email to be personable and approachable.

Personalize it with a name

By using merge tags, you can personalize the subject line for each recipient based on their own info. A merge tag is a bit of code that you’ll add to your email content. Your service provider will then replace the code with that bit of content. 

On Mailchimp, for example, use the merge tag *|FNAME|* to include the recipient’s first name. Using someone’s name can attract their attention in the clutter of the inbox. 

Watch the punctuation and capitalization

A subject line in all caps followed by three exclamation marks is a one-way ticket to the spam filter. Subject lines like this often don’t even see the inbox, but when they do, they get quick unsubscribes.

Add an emoji (maybe)

There’s some conflicting information out there about whether emojis help or hurt. A study by Search Engine Journal showed

• a slightly higher open rate for emails without an emoji in the subject line;
• a higher click-through rate for emails with an emoji in the subject line; and 
• a higher unsubscribe rate for emails with an emoji in the subject line.

So…what does that mean? Great question. 

I’d say it’s inconclusive, and that the success of emojis will depend a lot of your market, customer base, and overall subject line. 

In a conservative market, emojis may not be appropriate. But in hospitality, there is more room for a fun, informal tone, and emojis fit in well. 

Keep it short

46% of emails are opened on the itty-bitty screen of a mobile device. So keep your subject line length short to prevent it being cut off.

Most smartphone screens can only reliably show 50 to 60 characters, so that’s a good limit.

Like everything on this list, this is a guideline, not a rule. There are a few very successful email marketers that actually write very long subject lines. So if you’d like to experiment with both long and short, you should!

Don’t neglect preview text

Preview text is the short snippet shown right after the subject in your inbox. You have the chance to specify this text to further draw in the reader.

Most of this text will be cut off on mobile, so you can’t make your preview text vital to understanding the subject line. But on desktop, this extra space can help you catch attention. 

Test!

The best way to figure out what works for your industry and your email list is to test. A/B testing (aka split testing) is when you test two variations against each other to see which performs better. By sending the same email to a small portion of your list with two different subjects, you’ll be able to guage which subject performs better. Then you’ll send the email with the winning subject to the rest of the list. 

Email service providers make this easy. They’ll let you choose the percentage of subscribers that you want to participate in the test, and then will forward the winning format to the rest of the list automatically. 

Learn more about emails

There’s a lot more to learn about emails than just how to write a solid subject line.

Check out my 5-part email marketing series to learn about list building,

• Part 1: Build that List
• Part 2: The Welcome Email
• Part 3: 5 Tips for Better Emails
• Part 4: Email Optimization for Better Results
• Part 5: Simple Email List Management

Of course, if you’d rather just outsource this whole writing thing…