8 Types of Bad Email Subject Lines And What to Try Instead

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8 Types of Bad Email Subject Lines

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What is an email subject line if not your email’s first impression when it lands in a prospect’s inbox? And email campaigns are big business. Marketers sent over 838 billion emails in 2013 (that’s all the stars in the Milky Way times three). 

That’s 838 billion subject lines. And with that many emails landing in prospects’ inboxes, they’re getting savvier than ever. Crafting the perfect subject line can make or break whether your email is opened or not. 

Unfortunately, with all the pressure of an introduction on an email subject line, they can become incredibly stressful. 

It is easy to start overthinking. Is it too long? Not intriguing enough? Too generic? Should I use emojis? 

If you’ve ever wondered how to know what subject lines to avoid, you can follow these general rules to give yourself the best chance at a high conversion rate.

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8 Types of Email Subject Lines to Avoid (And What to Try Instead)

1. Subject lines with words and phrases that trigger SPAM filters.

When your email gets caught by SPAM filters because of spam trigger words in your subject line, it is the death knell of it. If your email gets caught, the chances that your prospect will open and read your email drops to virtually zero. Even worse, your chances of landing in a spam folder significantly increase.

One great step is to look up lists of words and phrases that commonly trigger SPAM traps and ensure you haven’t included any. Examples of such SPAM trigger words:

  • Earn $$$
  • 100% Free
  • Do it today
  • Don’t delete
  • Earn cash
  • Free offer
  • See it yourself
  • Urgent
  • Why pay more?
  • No cost
  • No obligation
  • Take action now
  • Important

email subject lines to avoid

These SPAM words will vary depending on your industry, but a quick Google search will turn up the biggest culprits.

Keeping in mind this list of words to avoid in subject lines is the easiest approach to follow and can make the most significant difference.

See also Writing Followup Sales Emails: 7 Steps To Becoming A Champion

Not only will it help ensure your emails make it to their destination, but it can help avoid triggering unconscious alarm bells that could make your prospect click away.

2. Subject lines that ask for time.

Time is the only finite resource. We can’t make more time. So when someone bestows their time to you, it’s a precious gift. Keep this in mind when drafting subject lines and try to avoid asking them for anything. 

This is especially true for cold emails. Your prospect doesn’t know you, might not know your company, and doesn’t (yet) care what you can do for them. 

Until they understand why you’re contacting them, any request for a meeting or call will feel like a chore. Worst subject lines to avoid like this include “Do you have 15 minutes?” or “Can we have a quick chat?”

3. Typos in subject lines.

Typos look sloppy and unprofessional. They can also give off an air that says, “Hey, I’m new!” If you aren’t taking the time to run a spell check before pressing ‘Send’, your prospects might wonder what else you will cut corners on. 

Grammarly is a great extension that’s free and checks your spelling on emails and websites.

4. Subject lines mentioning your company's name or some branded terms.

This comes down to clarity. Chances are, your prospect hasn’t heard your company’s name before. If they aren’t familiar with your company or branded terms, this will just create confusion.

You want the value of your email to be immediately apparent. You do that by putting the customer first. How? Use language your prospect will understand but not the language that makes people doubt and spam filters come into action.

Google and Apple have created billion dollar corporations using simple language that immediately conveys value. While it’s a tall ask, that’s what you want to do with your opening line.

5. Clickbait subject lines.

Just like with video or article titles, you shouldn’t put ‘clickbait’ in the subject lines to avoid category. A common tactic among digital marketers is putting “Re:” at the beginning of the opening line. 

This works by tricking a prospect into thinking there is an existing conversation. Essentially, you want to avoid subject lines that entice your prospect to click for the wrong reasons.

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Phew. Caps lock is the digital equivalent of yelling. While it might make an email standout in an inbox, it’s not in a good way. Using exclamation points falls into the same category. And it gets onto the list of one of the worst email subject lines.

7. Catchy subject lines.

The main goal of each email campaign is to land in the recipient’s inbox and be opened. Moreover, you aim to generate more leads, don’t you? So, you have no other choice but to just learn by heart all the words not to use in email subject lines when tailoring your splendid campaigns. These marketing-ish spam trigger words like “wanna have more revenue?” or “tired of your current CRM?” only add up to you being caught by spam filters and getting into junk folders. People do not appreciate you talking in a robotic manner with the use of spammy words. So, let’s try not to sound like a youtube ad that you hate yourself.

8. Using emojis.

Oh, please! Don’t use any emojis, especially in the opening lines. We strongly don’t recommend it. Your subject line matters for better engagement rates and emojis do not positively influence this. So, think twice if you’re a big fan of emojis. It’s not like trying to talk your friends into some adventure. Thus, it’s not only about words to avoid in email subject lines but also about symbols. You might think that emojis stand out in the inbox folder, grab the reader’s attention, and they immediately click your email. You’ve got it wrong as it does completely the opposite. Stay professional.

Read also: How to avoid spam filters when sending emails

Email Subject Lines. Getting it right.

Now that you know what subject lines to avoid, we’ve rounded up a few quick tips on what you should do when drafting the perfect subject line. If you review the eight types of subject lines and words to avoid, you might see one theme in common.

You want to avoid spam and not come off as too ‘salesy’ or even ‘spammy.’

See also: Effective cold email opening lines you should steal

These tips also follow a theme that will help you sound like a real person that can actually help.

  • Use spellcheck. Take a moment and download Grammarly if you don’t have it already.
  • Be short and relevant. Research has shown that subject lines under 50 characters have the highest open rates. So, the subject line should be short, but it also has to be strict and to the point. It should be relevant and show what this message is about and what’s there for them. This way, you are able to enhance your engagement rates as well.
  • Show value. The only thing that matters to your prospect is how you will make their life easier. Make this as obvious as you can in your subject line.
  • Personalise it. Nothing turns off a prospect faster than the feeling that you sent out a generic mass email. Personalise the subject line to speak to one person at a time to increase conversion by 6%.
  • Shout out connections. Did someone suggest you contact your prospect? Using a mutual connection to warm a cold prospect is a great way to entice someone to click ‘Open’.
  • A/B test. The best way to know what works and what doesn’t is to test it. Send out two groups of test emails, each with a different subject line. Which has the highest open rate?

See also: 5 Lead Nurturing Tactics to Get More Opportunities

Email marketing is still a powerful way to win new customers, spread the word about your company, and meet sales quotas (especially when you have software like Growbots on your side).

Learning to craft the perfect subject line that will get prospects eagerly clicking is worth the time investment.

Fortunately, the few quick guidelines outlined here will make it much easier to avoid the common pitfalls of bad email subject lines that get you triggered by spam filters.

If you’re looking for tools to help you evaluate your subject lines, then here’s a list.

Do you have a mental list of subject lines to avoid? Let us know which ones you can’t stand in the comments.

Picture of Marcin Szatkowski

Marcin Szatkowski

Outbound Strategy Consultant at Growbots

no prior experience & time required

Find your winning outbound formula with Concierge

no prior experience & time required

Find your winning outbound formula with Concierge

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