Here are ten common mistakes that will get your marketing emails falling into the spam abyss.

10 Reasons Why Your Marketing Emails Are Getting Flagged as Spam

Here are ten common mistakes that will get your marketing emails falling into the spam abyss.

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If people are not opening your marketing emails, it could be that your messages are flying straight into people’s spam box. Even if you only send mail to people who have subscribed to your mailing list, there are mistakes that you might be making that could cause your emails to get flagged as spam.

Email spam filters are designed to catch those annoying emails, like those that ask you to buy Viagra or send money to a Nigerian prince in return for a share of his fortune. These are emails that are sent out indiscriminately to thousands or millions of email addresses.

Spam filters often filter out legitimate emails as well. And, as many people do not check what is in their spam inbox, your marketing emails may not be reaching your target audience.

Here are ten common mistakes that will get your marketing emails falling into the spam abyss.

Your Headlines Are Too Pushy

Spam filters take several factors into account when filtering mail. One of those factors is the subject line. If your subject line looks too pushy or sales orientated, your marketing email might be consigned to the spam box.

Avoid making exaggerated claims in your subject lines. And avoid excessive use of capital letters and exclamation marks.

Try to think like your subscribers would think when they see your subject line in the inbox. Would you open your marketing emails, or would you assume they were spam?

Your Internet Protocol (IP) Address Has Been Flagged

If you have sent large volumes of unsolicited emails before, your IP address may have been flagged as a sender of spam on one or more of the domain name system blacklists (DNSBLs).

It might also be that the IP address of the email marketing service that you use has been blacklisted because of the actions of other people. You can find out if an IP address has been blacklisted by using online tools like or

If it is your IP address that has been blacklisted, you can apply to have your address removed from the list.

If it is your email marketing service provider that is on a blacklist, then you need to move to a more reputable service provider.

Your Physical Address is Not on Your Marketing Emails

It is a legal requirement in the US and many other countries that all marketing emails must include the physical address of the sender.

If you fail to add a physical address, your emails will likely be treated as spam.

If you do not want to put your physical address out there in the public domain, you can use a post box address instead.

Your Engagement Rates are Low

Your emails might be going to spam because you have had low engagement rates in the past.

If people have been ignoring your emails or deleting them before they have read them, webmail providers might have taken this as a sign that your emails are spam.

To improve your engagement rates, you will need to send higher-quality material to a better-targeted audience.

You Are Sending Emails to Inactive Mailboxes

If a high proportion of the email addresses you are sending mail to are not in use, it is a red flag to email providers because it suggests that you are sending emails blindly to arbitrary mailing lists.

To avoid falling into this trap, you should maintain your mailing list properly. Send out an email to users who have not engaged with your messages for a long time, asking them to respond in a certain amount of time if they want to remain on your mailing list.

If they fail to respond, remove that email address from your list.

You Are Not Giving Your Subscribers a Way of Opting Out

If you want to avoid being flagged as spam, you must give your subscribers an easy way to opt-out of your marketing emails.

Failing to provide a way to unsubscribe could land you with a fine in some countries, and it is another spam red flag.

You must also respond to subscriber’s requests to opt-out in a timely fashion. In the US, there is a legal requirement to remove subscribers who opt-out within ten days of them unsubscribing.

You Are Using Spam Trigger Words or Phrases

There are certain words and phrases that spam filters look for in marketing emails. If you are inadvertently using these trigger words and phrases, your emails will be sent straight to the spam box.

These spam trigger words include things like “great offer,” “check or money order,” and “risk-free.”

Quite simply, the trigger words are the types of terms that you expect to see in a scam or spam email. The only way to avoid getting consigned to spam because of these trigger words is to minimize your use of these types of aggressive selling phrases.

You Are Using Attachments

Sending marketing emails with attachments to a mailing list is bad practice because it increases the time it takes to open your messages.

Sending emails with attachments to many recipients is also a red flag to spam filters.

Cybercriminals use email attachments to spread viruses or ransomware. So, email providers will treat attachments as one of the signs that an email should be quarantined in the spam folder.

Inaccurate Sender Information

The email address that you send marketing emails from must identify who the sender is. Email providers check the sender’s email address to prevent spam emails being sent from spoof addresses designed to fool the recipient.

You cannot, for example, get away with sending emails from an address that, at first glance, looks like an official Microsoft address.

So, only send marketing emails from a legitimate email address that includes a real name and domain. Do not change the email address that you use for your marketing messages too often either because using multiple email addresses is another tactic that scammers use.

You Are Not Spellchecking Your Emails

Spelling mistakes and grammatical errors could also get the emails to subscribers flagged as spam. So, proofread your marketing messages and check your emails with a spellchecker and grammar checker before you send them.

A high proportion of spam emails are written by people whose first language is not English, which is why spam filters treat spelling mistakes and grammatical errors as a red flag.

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Email marketing can be a highly effective way of attracting customers. Even so, you must be careful that you do not get flagged as a spammer. Bear in mind the above points when you are drafting your marketing emails, and you should be able to stay on the right side of the spam filters.

Lori Ballen is an entrepreneur who makes money online through blogging, video, social media, and other content marketing strategies. She's a 6-figure affiliate marketer and coaches others on how to make money online. SEO, Search Engine Optimized Content is her specialty. Lori is the creator of Ballen Academy and owns a real estate business in Las Vegas, NV.

Lori Ballen

I teach bloggers how to grow their blog, and make money through multiple streams of income. From affiliate marketing, to building courses, I share 7 income stream strategies through blogging.

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I regularly publish guides, articles, videos, and live events for digital marketers. As a 6-figure affiliate marketer, and blogger, I enjoy sharing my strategies. 

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