If you are thinking about releasing a spam campaign, then forget it: these campaigns will get you no results. Are you still considering it – especially because it is so much easier and cheaper to spam than launch a 
legitimate email marketing campaign? Consider this: spam hurts your business’s reputation, pushes potential leads away from you, and still wastes resources which could be used for productive purposes. Further, spamming is illegal and can get you a fine of $11,000 per violation – meaning one bulk spam mail could cost you millions.
Even if you aren’t spamming, there is a good chance that your email marketing campaign finds its way into a lot of spam folders. In fact, about 15% of all email marketing campaigns wind up in spam folders – even when the recipient opted into the email list. The reason for this isn’t because the recipient doesn’t want to get your mail (they could be eagerly awaiting your email). Rather, the email provider’s spam filters automatically check emails to weed out spam.
Whenever you receive an email, your provider is using a spider to crawl through the content and determine whether the email is spam. There are many parameters which these crawlers use and they differ depending on the email provider. However, these are some of the most common features which would identify your email as spam:
• Use of all capital letters (particularly in the subject line)
• The term money occurs frequently
• Use of particular phrases which have been identified with spam, such as “click here” or “don’t wait” or “breakthrough discovery”
• Using reds or greens for the fonts
• HTML emails, particularly if they are coded badly or just an image
• Putting the word “test” in the subject
If you have some of these features in your email, don’t worry. The spam filter will assign your email points for each of the spammy features it has. A few spammy features are not going to get your email campaign put in the spam folder but a lot of spammy features will definitely get you there.
Always make sure that you pay attention to your metrics when running an email marketing campaign. If a lot of your emails are not getting opened, it is likely because they are in the spam folder. Once emails are marked as spam, you may get blacklisted in future emails, regardless of how un-spammy they are. The best thing to do is make sure you are designing great email campaigns from the get-go to avoid the spam filters completely.