5 subject line mistakes that are killing your open rates

Email marketers know that success begins with a subject line. After all, the subject line is what entices a subscriber to open, read, and click-through your emails.

Most subscribers receive upwards of 121 emails per day, according to Radicati. With this many emails coming into the inbox, you need subject lines that stand out.

Even though you have the best intentions, you may be making mistakes with subject lines that negatively impact your engagement rates. Being overly formal, neglecting to personalize, and lack of testing can all cause subscribers to delete your emails before they get read. Thankfully, these mistakes are usually easy to fix.

Today, we’re sharing 5 subject line mistakes that are killing your open rates, along with info on what you can do to improve.

Mistake #1. Writing like a business

Although your brand is dedicated to marketing services and selling products, formal emails that feel too corporate are unlikely to break through inbox clutter. Using marketing jargon is a mistake. In fact, including the word “newsletter” in your email subject lines decreases the click-through rate by 30%.

Thankfully, this mistake is easily solvable. Rather than writing like a business, focus on making your emails sound as though they’re coming from a friend. For example, you can punch up your subject lines with the use of emojis:

  • 😍 50% OFF ALL dresses 😍
  • ⛵ Sail away with these ⚓ nautical ⚓deals
  • The jeans everyone 💖's | 40% OFF
  • 🍎📏Getting you ready for Back to School 📚

Emojis instantly make your subject lines casual, relatable, friendly, and enticing. Brands that use emojis have seen a 56% increase in their unique open rates.

You can sound friendly by using contractions (don’t instead of do not), personalizing your messages, experimenting with upper and lowercase, and using easy to understand vocabulary.

Mistake #2. Neglecting to personalize

Did you know that emails with personalized subject lines are 26% more likely to be opened? When sending out an email, it’s easy to create one compelling subject line for your entire list. But it’s worthwhile to consider how you can personalize your subject lines so that they’re personalized to the subscriber.

You can do this in a number of ways. You can simply add a first name to a subject line, like Lord & Taylor.

Lord & Taylor – Email Subject Line – Personalization - Name

You can also personalize based on product recommendations, like Sephora, who promises to deliver makeup recommendations in the appropriate skin tone.

Sephora – Email Subject Line – Personalization – Product Recommendations

Here are a few clever ways to personalize subject lines:

  • Geography: Include a subscriber’s city, town, country, or region within the subject line.
  • Past purchases: Use a past purchase to personalize the message. For example, use the subject line to ask a subscriber “How is your new Benefit lipstick?” instead of “How is your new product?”
  • Customer status: If a customer is a VIP with a certain number of rewards points, highlight this in the subject line.
  • Behavior: When a customer adds an item to their shopping cart, send a personalized email with their name and the product they’ve selected.

Mistake #3. Lack of experimentation and testing

As a marketer, many decisions rely on a sense of intuition. However, every subject line can (and should) be tested. A/B testing provides an easy way to find out which subject lines have the most impact and drive the most engagement.

Most email service providers make it easy to test two different subject lines. You can automatically send out two different subject lines to a small subset of your list (50% of this subset will receive one subject line, the other 50% will receive the other). Whichever subject line receives more opens will dictate which subject line is used for the rest of the list.

Emma - A/B testing subject lines

For example, we tested two different subject lines for a new year campaign. We found that “Let’s do this, 2017” performed better than the other option. Even though this subject line may have stood out because of the emoji, we think the powerful thing here wasn’t necessarily the emoji, but rather the length. 

When it comes to subject lines, you can A/B test two different options against each other to find out which resonates with your subscribers. The results may surprise you.

Mistake #4. Forgetting the power of pre-header text

Many marketers either forget or neglect their pre-header text, which is the text that is displayed in inboxes alongside the bold subject line. This mistake doesn’t have to do with the subject line, exactly, but it’s an essential component of crafting a subject line– and it’s often forgotten.

Pre-header text can provide powerful, contextual information to a subscriber. The copy can complement the subject line, helping the subscriber to understand exactly what they’re getting. 

For example, Amazon illustrates why “creating a pet profile” is so important using the pre-header text. They offer up a “why” next to the subject line, offering a compelling reason– unlocking personalized pet product recommendations– for subscribers to open and click.

Amazon - Pre-Header Text

Similarly, Brooks Brothers uses the pre-header text to give the most important information, which is that the spring and summer clearance is 50% off. In this example, the subject line is purposely vague, while the pre-header text provides the context that is likely to make someone open and read.

Brooks Brothers - Pre-Header Text - Discount

Mistake #5. A broken experience

A broken experience is one of the biggest mistakes you can make with your subject lines. If the subscriber sees spelling errors and typos, broken personalization, or unsupported characters, they’re not going to open your messages.

Unfortunately, you can inadvertently create a broken experience by accident. That’s why it’s essential to test emails across a variety of browsers and different devices.

Here are a few things to watch out for:

  • A subject line that doesn’t match the email content
  • Forgetting to replace placeholder text
  • Spelling errors and typos
  • Personalization that’s flat out wrong
  • Unsupported characters
  • Lengthy subject lines that get cut off

No matter what you do, occasionally you may make a mistake and accidentally send out a broken subject line. Mistakes happen, so don’t panic. Simply make sure that you have systems in place (such as checklists) to prevent these occasions from happening often.

Have you made any of these mistakes with your subject lines? What steps have you taken to improve? Share away in the comments!

About the Author

McKenzie Gregory is a senior content manager on Emma’s marketing team. A Nashville native, she can be found covering all things email on the Emma blog, debating hyphenation rules, and watching obscene amounts of Netflix without a trace of shame.

More Content by McKenzie Gregory

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