According to Radicati Group, in 2015 there are over 205 billion emails sent worldwide per day, of which more than half are business emails. In average, one should consider that a 30% open rate in email marketing is pretty good. That means in 10 emails sent to inboxes, only 3 may got read, not to mention the click through rate of only 6% is expected.

So what open rate would it be if your emails land in customers’ spam boxes? Based on numbers above, I would confidently say that they shall never get seen, opened and finally be deleted months later. Email ending up in spam boxes is, for sure, on the top of common mistakes that break your email marketing.

Why is your email vulnerable to jumping into spam boxes?

Spam filters of email provider services are getting more sophisticated and effective in helping people receive the right emails, save time and work more efficiently. Poor promotional and advertising emails will get a very low chance to reach people thanks to these advancing spam filters.

One main element based on which spam filters work is triggering words indicative of spam content. Below are 81 spam words highly vulnerable to spam filters that you should avoid in writing the subject lines and content of emails in business.


Together with avoiding spam trigger words, there are many other tips to prevent emails from landing into junk boxes, to name a few here:

  • Break large lists down:
    Spam emails are usually sent in huge mass at the same time. If you have a big list of customers, segment them into smaller groups to schedule emails at different time to avoid being marked spam by email service providers.
  • Be cautious with HTML code:
    Spam filters spot bad html codes, especially those done in Microsoft Word or by placing plain text in an element intended to be rendered as HTML. Most people not familiar with professional coding will therefore be prone to creating sloppy HTML templates, resulting in emails sent to spam boxes. For those, it is highly recommended that they should count on professional email providers for well-formed default HTML.

(For online store owners: 07 featured email campaigns of MailBot app are well-coded HTML email templates, prepared for selling and engaging email marketing campaigns)

  • Avoid using big images with little content:
    It is a bad idea to embed emails with large images because spam filters do look for types of image-based emails without text content. Thus, do not include too many large images in your emails, but maintain a good text to image ratio ( it is suggested that at least 2 lines of text should be added for every graphic).

For more tips in doing email marketing the most efficient ways:

Follow my series of blog posts in Email Marketing here. If you are already a MailBot customer, I will send a series of killing tips to win sales and customer’s heart to your private inbox, exclusively.

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