Why Are My Emails Going To Spam? A Marketer’s Guide

Why Are My Emails Going To Spam? A Marketer’s Guide

Picture this: It’s the moment you’ve been preparing for. You’ve set up email automation for your marketing campaigns. You’ve hooked up your app with a platform to send transactional emails.

Your marketing team worked diligently on the copy and graphics. You hit send, and the next thing you know… the email is redirected by spam filters, straight into the recipient’s spam folder! 

So, the big question is, "Why are my emails going to spam?"

We’ve consulted the experts and rounded up 9 key reasons why your business marketing and transactional emails are being treated as spam emails and diverted to recipient spam folders.

This article covers all the primary factors that impact on your emails’ going to spam or being delivered, including handy prevention tactics to improve your email deliverability. It's time to put an end to all of the frustration and ensure that your emails end up where they belong, right in your recipients’ inboxes.

For a quick intro to the topic of avoiding the deadly spam box, watch the following the following video by Alex Berman.

1: You’re not setting up proper email authentication

One of the leading reasons for emails being flagged by spam filters, and for emails going to spam, is that they aren’t compliant with the required authentication processes. 

Email authentication techniques are used to prevent email fraud, improve email deliverability, and ensure continued delivery by providing information about a sent email’s origin. 

This process further confirms that the email was indeed sent from the sender listed in the “from” field and wasn’t tampered with while in transit or sent by an imposter.


Prevention is better than cure, so instead of wondering "Why are my emails going to spam?", take the time to implement proper email authentication methods before sending email.

There are four main methods used by ISPs: SPF (Sender Policy Framework), DKIM (DomainKeys Identified Mail), DMARC (Domain Message Authentication Reporting and Conformance), and BIMI (Brand Indicators for Message Identification).

The DKIM and DMARC methods are especially noteworthy. DKIM provides an encryption key and a digital signature that verifies an email’s authenticity by checking for forging or alterations that would prove otherwise. You can read more about how DKIM works and how to set it up here.

DMARC establishes ways that allow the domain owner to publish their email authentication processes, states which actions to take if an email were to fail authentication, and/or warrant the reporting of these actions taken on an email falsely claiming to be from the sender’s domain.

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2: Your sender info is inaccurate or misleading

Of the many factors that contribute to a successful email is sender-trustworthiness, and it is of the utmost importance when it comes to determining whether an email will be opened or not—or whether it will end up in a spam folder.

If the recipient doubts your sender info (the sender name and the email address that the received email came from), authenticity, and content, they may mark your email as spam (which will send all your emails straight to the spam folder), block your address, or unsubscribe from your list. 

Of course, any lack of trust will make the recipient less likely to accept your mail and, if they consign your email to the spam folder, this represents a complete loss of contact and opportunity for your business.

The solution

Choose an appropriate sender name. Depending on the use case, a good name would be your “Company name” or “First name from company”. It should also match the email address and the signature found within your email body.

It’s also essential that you send different types of emails from the correct business email domains. For more insight into this topic, please Read This.

so frustrated

3: You’re using misleading subject lines

The nature of your subject line can determine the destiny of your email and whether or not it lands in your recipient’s inbox or in that bad old spam folder.

It is recommended that you aim to catch the recipient’s attention while avoiding commonly used tactics that cause an email to be blocked, flagged by spam filters, or sent to spam.

For instance, if your email is inconsistent with what you suggested in your subject line, your prospects are likely to unsubscribe or tag it as spam and complain. 

In addition, intentionally misleading people with your subject line in order to get them to open your email is not only unethical but illegal in many countries including the United StatesCanada, and most of Europe (and many other countries).

The solution

Honesty is the best policy when attempting not just for your email to not only bypass spam filters and land in the recipient’s inbox but also to get your marketing email opened. 

Create a compelling, fun, personalized yet sincere subject line directly related to the content of your email. That way, your customers will feel that they’ve made an informed decision on whether or not to prioritize your email.

spam cutouts

4: You’re using spam triggers

As an email marketing manager who doesn't want to send spam email, it's important to understand how spam filters work, because it will help you create email messages that are less prone to deliverability issues and more prone to being read! 

Spam filters are used to wipe out junk from your customer’s inbox, but they can sometimes do their job so zealously that they send even the most innocent of emails to the spam folders too. 

Many emails that are flagged as spam are flagged as such due to a spammy subject line or spam-triggering content and design.

Spam filter flags are raised by spam trigger words like  “Congratulations” and “Free”, as well as a myriad of other factors. 

Be advised, there are hundreds of spam trigger words that could get an email flagged, and when they are used in conjunction with spam trigger symbols like “@” and “!!!”, they are even more likely to alert spam filters.

Hence, your choice of words and punctuation is crucial to avoid life in the spam folders. Poor grammar, misspelled words, writing in ALL CAPS, and using an excessive amount of exclamation marks or emojis, are all common triggers that will alert most spam filters.

The solution

Avoid using those spam trigger words and trigger symbols mentioned above, and don’t begin your subject line with “Re:” or “Fwd:”. 

Don’t use spam words and symbols such as “great offer” or the “$” sign, and always proofread your emails before you hit the send button. 

Simply make sure that your email doesn’t look like it was written carelessly, to trick people, or generated by a computer, and you’ll be far less likely to trigger spam filters.

For further insight into spam trigger words, symbols, and emojis to avoid, watch This Video by creator, Kerry Egeler.

For more insight into marketing and transactional email best practices, explore our latest posts.

spam trigger

When sending marketing emails to people without their permission, you seriously boost the chances of your email ending up in the recipient’s spam folder. 

This behavior is counterproductive, and a waste of your time altogether. Only send emails to recipients who’ve consented to as much, or you’re setting yourself up to be consigned to that spam folder! 

By conducting email marketing without consent, you put your email marketing emails at risk for lower open rates, getting stopped by spam filters and flagged, not to mention the violation of anti-spam and pro-privacy laws such as GDPR, CAN-SPAM, and CASL.

The solution

To avoid negative reviews and spam complaints, and to increase the chances of emails being opened, you should only be sending messages to those who have provided consent to receive them. 

In order to do so, you must obtain confirmation from them. A widely used and recommended way to ensure consent is through the use of a double opt-in system where a user signs up for an email marketing list and an email, which includes a link to click and confirm the subscription, is sent out to them. 

It is only after they’ve hit “confirm” that you’ve obtained explicit confirmation to send them emails. Note that double opt-in is not a legal requirement, but is just a good practice. 

Don’t forget to make sure that recipients can always unsubscribe or change their email settings regardless of their initial consent. To do this, always include an unsubscribe link at the bottom of your emails.

All email marketers should remember that, unless you provide an unsubscribe link at the bottom of your emails, you're essentially sending spam emails, because you're not considering the recipient's needs and wishes.

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6: You’re not monitoring your email list

If your mailing list contains an excess of inactive or disabled accounts, sending emails will result in what’s called a “bounce”. 

To clarify, inactive accounts are valid email addresses you may have previously emailed to, but that now can’t receive your email, most notably because they’ve hit their inbox quota, or have been disabled or deleted. 

Too many bounces will result in lowering your sender reputation, which may eventually land you in the spam zone.

The solution

Monitor and update your email list as a routine segment of your workflow.

  • Monitor for bounces and be sure to remove bounced email addresses from your recipient lists.

  • Depending on your use case, find email addresses that have not engaged with your communications over a substantial period of time and remove them from your email list.

no more spam

7: Email design spam triggers

While content conveys important information, design is what really catches the recipient’s eye. Beware, however, as certain email designs can catch the unwanted attention of the spam filter, just like certain spam trigger words can get your content flagged. 

Poor email layouts and designs that can trigger spam filters include large images (since spammers like to use an entire image instead of text) and HTML that’s not adaptive to the reader’s screen or that intentionally leaves content out of view.

The solution

There are many design methods that will help you to produce a more engaging transactional, promotional, or marketing email, but the following will help you do just that while avoiding the spam box:

  • Ensure your email isn’t wider than 640px.

  • Keep images as small as possible and your content as concise as possible.

  • Add alt text to your images.

  • Keep a maximum ratio of 60% text to 40% images.

8: You have low to no sender reputation

Email sender reputation, including IP reputation and domain reputation, is a score that is assigned to a domain or an IP that sends email. It’s a crucial component impacting your email deliverability.

8a) No reputation

When you start out sending emails, you begin with a clean slate and no email, IP, or domain reputation, so you're more likely to be flagged as a spammer if your email behavior seems off. 

Some bad email behaviors include sending 1000 emails per minute, bad email lists, low-quality content, and more.

The solution

Start off gently and warm up your domain and IP addresses. Don’t forget to add authentication methods to your email domain, and work on avoiding all of the other reasons mentioned here.

8b) Low reputation

If you manage to send enough emails but are left with a low reputation (due to one of the other reasons mentioned here), you'll have to raise your reputation.

The solution 

To achieve this, you have to start by finding the root of the problem and fixing all of the relevant issues. Then, figure out how to get the ratio of complaints/bounces:sent emails low again.

By following these guidelines, you should now be well on your way to sending properly authenticated, honest, explicitly confirmed, and proofread emails that will surely earn their rightful spots in the recipient’s inbox.

For further insight into this topic, and simple steps to help improve your email deliverability, please Read This.

9: You’re not using a reliable email service provider

Email service providers apply varying levels of security to their email ecosystems, making emails sent via certain providers inherently more secure than others, and inherently more deliverable. 

By using a verified, authenticated, and secure email service provider like Mailer To Go, you significantly increase the chances of your emails bypassing security spam filters, and landing in your recipients’ inboxes—instead of in their spam folders.

The solution

We get it, you don't ever want to ask "Why are my emails going to spam?" again. So, if you're looking for the most efficient route to stop emails from going to spam and to ensure that both your transactional and marketing emails reach your customer’s inbox, try our simple, secure, scalable, and automated email delivery service, Mailer To Go.

Click here to find out more and give it a try.

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Frequently asked questions

How do I stop my emails from going to spam?

To stop your marketing, promotional, and transactional emails from being flagged by spam filters and sent straight into recipient spam folders, follow these best practice tips. You'll never wonder "Why are my emails going to spam?" again:

  • Set up proper email authentication.

  • Use accurate and honest sender information.

  • Use a forthright, sincere subject line.

  • Avoid spam trigger words, phrases, punctuation, symbols, and emojis.

  • Never send unsolicited emails.

  • Monitor and review your email list for inactive or disabled accounts.

  • Watch your email layout and content for design-based spam triggers.

  • Build a good, noteworthy sender reputation.

  • Use a reliable email service provider to improve your email deliverability.

How can I tell if my emails have gone to spam?

First, you could try using a third-party tool like This to obtain a score on the “spamminess” of your email. While these tools are great for detecting bright red flags, there’s no foolproof way to tell if your marketing or transactional emails are reaching recipients’ inboxes. 

The best way to know whether your emails are reaching their mark is to ensure they do, and that means understanding the 9 top reasons why your emails go to spam, along with the appropriate solutions to those issues.

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