avoid email spam filters

Email newsletters are a critical tool in the armoury of every online publisher. They should be used both in the sales process and to build loyalty. Therefore if you find that a lot of your emails are not being delivered you must take the time to understand why.

The number one reason why email newsletters don’t get delivered is because they are blocked by spam filters.

Therefore it’s important that you know why this is and how you can reduce the chance that it happens.

Spam filters are like bingo cards. The have a checklist and if an email ticks enough boxes on the scorecard … bang … the door is slammed in its face.  Unfortunately every spam filter is slightly different.

However, if you follow these guidelines your newsletter should slip past the gatekeeper every time.

1. Use a reputable email service provider

Choose a reputable email service provider that has a good reputation for email deliverability. This will increase the chances of your email being delivered to your subscribers’ inboxes and not getting caught by spam filters.

2.  Avoid spam trigger words

Spam filters look for certain words, phrases, layouts and email characteristics.

The number one cause for blocking an email is the use of words that commonly appear in spam. Some are obvious like “free”, “Viagra”, “cash” or “discount”. Some are not so obvious like “opportunity”, “amazing” and “compare”.

3.  Use a clear subject line

Every spam filter is weighted to take a long hard look at the subject line. Use a clear and concise subject line that accurately describes the content of your email. Avoid using any of the spam filter words in this sensitive field. Avoid using all caps, excessive exclamation points, or misleading subject lines.

4.  Text-based emails are best

Many email newsletters are html with lots of images. They look slick and professional as marketing material should. However be aware that html emails are more likely to get blocked. Good email services will create a version of your newsletter in both html and plain text to increase the chance of getting through.

5.  Don’t include too many images or links

Some emailers put their whole message in a big image; big mistake. Not only the spam filters likely to take an immediate dislike to the email, but also a lot of firewalls are programmed to strip images out so recipients can end up with a blank page. Using too many links in your email can also trigger spam filters. Make sure to balance the text and images in your email and only include relevant links.

6.  Avoid attachments

Many viruses are hidden in attachments so spam filters and firewalls are often programmed to block attachments from unknown email addresses. Avoid attachments if you can.

7. Use a recognizable sender name and email address

Use a recognizable sender name and email address to increase the chances of your email being opened and not marked as spam.

8. Don’t use color text and background colors

If you use color text or color backgrounds in your newsletter, the spam filters will wag their fingers and look for other questionable characteristics and reasons to block you.

9.  Build a clean email list

Make sure you have a clean email list by removing inactive subscribers and avoiding purchased email lists. A high number of bounces, spam complaints, or unsubscribes can negatively impact your email deliverability.

10. Include an unsubscribe link

Include an unsubscribe link in every email to make it easy for subscribers to opt-out of your email list. This can help prevent spam complaints and improve your email deliverability.


By following these tips, you can help ensure that your email newsletter reaches your subscribers’ inboxes and not their spam folders.