Email Marketing Don’ts: Phrases That Trigger Spam Filter


Writing a subject line and content for your email can be one of the greatest challenging phases of email marketing. Particularly, when you’re trying to escape spam trigger phrases and words. A spam filter can be initiated for several reasons, affecting your email messages to skip receiver’s inbox. It will directly be sent off to the Spam folder. However, spam filters can be bypassed. One of the easiest techniques that every marketer uses is cautious picking of words for the subject lines. These words that trigger spam filters cause problems and there is a higher possibility that your email will be trapped and marked as spam.

According to Deliverability Benchmark Report, only 21% of emails go to inbox. If you need to send a thousand of emails, it means 200 clients will not receive it. That’s a lot, right? By escaping these words when writing an email subject line, you can intensely increase your probabilities of reaching the potential client. So to help you in your email marketing, there are listed below some of the words and phrases that trigger spam filter:

  • This is not a scam
  • Eliminate bad credit
  • Subject to credit approval
  • Money or Check Order
  • Print out and fax
  • Act now
  • Call now
  • Your Income
  • Act now! Do not hesitate
  • For Instant Access
  • Multi-level Marketing
  • Free grant money
  • No age restrictions
  • Brand new pager
  • No medical exams
  • Cannot be combined with another offer
  • Have you been turned down?
  • Once hundred percent free
  • One hundred percent guaranteed
  • Claims to be in accordance with some spam law
  • Collect Child Support
  • Info you interested
  • Confidentially in all orders
  • Long distance phone offer
  • Earn extra cash
  • Lowest insurance rate

Words to Avoid:

  • Unlimited
  • Free
  • Spam
  • Winner
  • Purchase
  • Open
  • Obligations
  • Name
  • Luxury
  • Limited
  • Request
  • Lose
  • Problem
  • Trial
  • Satisfaction
  • $$$
  • Income
  • Congratulations

Furthermore, aside from eliminating these phrases and words from your email’s subject line, you also need to consider how exactly you write it.

  • Do not use all caps when writing a subject line
  • Check spellings and proofread your content before sending
  • Do not use JavaScript, Flash, and Video
  • Do not put an exclamation point in your email’s subject line
  • Do not write a single word subject line
  • Do not insert forms into your emails
  • Do not add the word “Re” in your subject line, especially if it is not a reply message
  • Avoid adding too many links that are labeled with “click here”

Other Important Things to Deal with to Avoid Spam Filters

  1. Keep An Eye On Your Email Reputation

Not only engagement metrics you should follow, but also check your email reputation from time to time. It is useful to know if someone issued a spam complaint or if you got spam trapped. You will simply know how your emails are being seen by customers. There are several tools that give the score from 0 to 100 to your email by checking your IP, like Sender Score or others.

  1. Choose A Trusted Email Service Provider or ESP

Every ESP acquires good reputation depending on the good standing of their customers. If a particular ESP client sends out relevant and valuable content the ESP itself become trustworthy. So if you want to avoid spam filter, you should go for email service providers such as Hotmail, Yahoo! Mail, or Gmail.

  1. Use a Noticeable Sender Name

When sending an email message, it is always a good practice to add your personal name along with your brand or company, so that receivers will recognize you easily. Why? Because, each of them receives hundreds of emails every day, and they decide which one to open. For sure they will first open the email that looks important.

  1. Keep Your Email Lists Clean

In order to avoid spam filters and traps it is very important to clean your email list regularly. Here are some helpful tips to keep your email list clean.

  • Do not purchase an email list
  • Get rid of Hard Bounces from your Email list
  • Monitor Feedback Loops
  • Remove Inactive Subscribers
  1. Avoid Adding Too Much Media Content

The majority of email clients don’t want to receive a message that is loaded with media content like Flash and videos. Some of them don’t even support so much data inside the email.  This often happens with interactive email, which is going to be a trend of Email Marketing 2018. For example, iOS Mail App and Apple Mail have a great support of email interactivity, and the same is hard to say about Gmail and Outlook. Check the Interactivity support table on Email on Acid.


Unluckily, there is no guarantee that your email messages would not directly land into a spam folder. However, by cleaning your email list, taking care of technical issues, and being cautious in writing subject lines you will be able to protect your email from spam filters and secure your domain and IP address from getting blacklisted.