Spam – Avoid Having Emails Flagged As Spam

Check Your Message With An Online Service
You can use the SpamCheck service to determine the Spam rating of your message. Send your newsletter to with TEST as the first word in the subject line. In a few seconds you will receive a SpamCheck Report with suggestions regarding the newsletter content.

Avoid The Following

  • Phrases and wording spammers commonly use.
  • Using all upper-case words in the message subject.
  • Do not use (too) many images.
  • Properly balance your pictures size with the text size.
  • Avoid using HTML tags that could increase your spam score, e.g. iframe tags, multiple large font tags and/or color font tags (better use inline CSS styles instead).
  • Using scripts in your messages, like javascript, vbscript.
  • Correct any HTML coding errors in your messages, since these too will increase your spam score.
  • Only Send Acceptable Attachments
    Be careful with sending attachments other than .pdf, .gif, .jpg and .png files. Attachments like .zip, .avi, .swf, .exe, etc., may trigger spam filters or anti-virus checkers.

    Do Not Use Third Party Sending Services
    Sender Reputation: Your sender reputation is a number or score assigned to your sending IP or source. It’s believed that it’s also combined with domain name and several of the factors listed below, but the actual algorithm remains a secret. If you are using a third party email marketing platform such as Comm100, it’s important that you select a service that has a high sender reputation and that protects its sender reputation by ensuring that its clients don’t send spam emails.

    Make Sure Your Emails Are Of Interest
    Activity of Your Email List Subscribers: Another more recent development in spam filters is to apply a score based on the activity of your email list. If your emails regularly get incredibly small open rates or are deleted without being opened, then that indicates to email service providers that you are sending low quality email that is potentially unsolicited. While it won’t automatically get you blocked from the inbox, it will combine with other scores that may reflect unfavorably on you.

    Watch Your Subject Line
    Subject line will be a huge determinant to your email’s ability to get into the inbox. It’s the first thirty-five to fifty characters of an email subject line that users see. The reality is that you should not write an email subject line that is significantly longer than that because the longer your email subject line is, the more likely it would be flagged as spam.

  • Shorter is better! (But not less than five or six words)
  • Don’t rely on words that are viewed as spam.
  • Avoid using all caps or special characters in your email. They may end up resulting in having you flagged as spam.
  • Minimize The Use of Images
    Emails that are one large image have a high chance of being flagged as spam. Using a large image to encompass the entire email is a frequent trick of email spammers. If the entire content of your email is in an image file, then the email spam filters have nothing to spider in terms of content and can’t figure out if your message is junk or not. While images are an important part of any email template, the more images you use the more you may experience spam filter issues. If you are having a difficult time making it into the inbox, then one of the first steps you’ll want to explore is to reduce the number of images in your email template. Do not use templates with multiple images.

    Minimize the Use of Red Fonts and Huge Headline Size Fonts
    Red fonts and huge headline size fonts have also been shown to cause spam filter issues, though not as frequently as many of the other issues noted here. As a general rule, it’s just a better idea to avoid using red fonts (pick an off-red color), huge headline fonts of more than sixteen pixels or a combination of both. There are plenty of design options that still give you great flexibility without using those font sizes and colors.

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