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5 Embarrassing Subject Line Mistakes to Avoid


Subject lines are incredibly powerful. That’s because they are one of the first things that subscribers look at when they receive an email and are trying to decide whether to open it. The subject line is second only to your sender name in importance, as you’d expect with a permission-based channel like email.

Marketers are clearly aware of the power of subject lines, but their efforts are often inconsistent and their results mixed. For instance, subject lines are the most A/B tested email element, according to Litmus’ 2017 State of Email Creative. But many of those tests are undermined by wrongly using open rates to determine the winner, rather than deeper metrics like conversions.

Also, some marketers believe in the power of subject lines so much that they think that:

Despite all of the (mostly justified) power attributed to subject lines, this line of text is a hotbed of mistakes that can distract and confuse subscribers and be embarrassing for the brand. We discuss five such mistakes in this slidedeck and share numerous real-world examples.

These subject line mistakes made me cringe! Check out these real-world examples from @litmusapp >>

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The subject line is a make it or break it moment for marketers. You have only a few seconds to earn a subscriber’s attention. Don’t squander the moment by making a distracting error.

If you don’t have a good QA process in place, you could end up accidentally making one of these 5 embarrassing subject line mistakes…

  1. Not overwriting placeholder text
  2. Typographical errors
  3. Broken personalization
  4. Improperly inputted or unsupported emojis and special characters
  5. Awkward truncation

Let’s look at each of these mistakes, along with some real-life examples, and then talk about some recommendations on how to avoid them.

1. Not overwriting placeholder text

If you don’t have a good QA process set up, placeholder text can accidentally sneak through and get sent to your subscribers. For example…

Timberland subject line mistake
COMPLEX subject line mistake
HP subject line mistake
Musician's Friend subject line mistake

2. Typographical Errors

Typos are distracting and sometimes quite embarrassing. An unnecessary space (or a lack of spaces) can also cause problems. For example…

Carnival Cruise Line


3. Broken Personalization

When the personalization in your subject line breaks, it makes your email seem artificial and impersonal—the exact opposite of what you were going for. For example…

Bungie subject line mistake
Airbnb subject line mistake

4. Improperly inputted or unsupported emojis and special characters

Emojis and special characters aren’t supported in every email client, and can look different even when they are supported. Also, if they’re added incorrectly, you can end up with code in your subject line. For example…

Rio subject line mistake
Miracle-Gro subject line mistake
St. Jude subject line mistake
Victoria's Secret subject line mistake

5. The awkward truncation of a subject line

Having the text of your subject line get cut off in the inbox can appear to change your message in ways that are distracting, confusing, or even super embarrassing. For example…

Gilt subject line mistake
Brooks Brothers subject line mistake
SeaWorld subject line mistake
ASPCA subject line mistake
Express subject line mistake
Clinique subject line mistake
Cafe Rouge subject line mistake
Victoria's Secret subject line mistake
Yahoo Sports subject line mistake

If any of those examples made you cringe, consider adding the following to your pre-send checklist…

  1. Double-check the spelling, grammar, and content of your subject line.
  2. Ensure your personalization is working and has default values set.
  3. Preview your subject lines in all the popular email clients.

The Litmus Email Creative Platform can make this quicker and easier. Our Subject Line Checker provides:

  • Real-time previews of your subject lines and preview text in 15+ email apps and webmail clients
  • Alerts about issues that could hurt your email’s performance, like unsupported emojis and character counts

Subject Line Checker is just one of the many features available in Litmus Builder, the code editor we designed from the ground up specifically for email development.

To discover how Subject Line Checker, Builder, and the rest of the Litmus Email Creative Platform can improve your subscriber experience…

Start a free trial →

Chad S. White

Chad S. White

Chad S. White was the Research Director at Litmus