· 21 min read

Why Do Emails Go to Spam Instead of Inbox & What to Do So They Don’t Anymore

After reading this article carefully, you will be able to understand why emails go to spam instead of inbox and what you can do to increase your inbox placement rate.

Let’s start with the basic definition of email spam, also known as junk email: unwanted messages sent in bulk. The term spam means unavoidable and repetitive.

ISPs continually control a bunch of email addresses to see their open rates, inbox placement rates, bounce rates, and other related scores in order to provide a service of flagging some emails as spam.

email marketing 2020

Email statistics for a better understanding of the importance of email marketing are given below. The numbers show that a successful email strategy is a key point for increasing sales and getting qualified leads.

The number of email users are 3.9 billion in 2020, which means that more than the half of the world's population is using email as a communication tool.

  • A current study by Return Path shows that in 2020, the average inbox placement rate is 83%, which contains emails sent within companies.
  • 86% of business professionals prefer to use email when communicating for business purposes.
  • About 49% of businesses use some form of email automation.
  • Email marketing spending in the United States would grow from 2.07 billion U.S. dollars in 2014 to 3.5 billion U.S. dollars in 2020.

As you can see, email marketing is one of the most engaging methods for growing your business and customer base.

A lot of people are still having some trouble with email marketing. Generally, they complain of being considered as spam. Thankfully, after reading this article, you’ll understand the main reasons behind that situation!

I hope you find it useful, and if so, please don’t forget to share your experience in the comments below.

Enjoy your time!

The Journey of an Email Sent;

Emails reach the destination from their origination point through the Internet. Of course, this systematic process includes some complex metrics.

This process is significant because our emails are determined as doubtful or trustworthy based on some features.

a girl working on her computer and her email goes to spam

Most of them get blocked on the gateway and never reach the spam folder or inbox folder. That means emails that pass the gateway have high sender reputation, relevant content and user engagement.

So, let’s discuss some reasons why your emails go to the spam folder instead of the inbox folder and how to fix this situation in the best possible way!

1. You Have An Email Spam Filter Issue

Mailbox providers use inbound and outbound emails to prevent spam but email senders are mostly concerned with inbound filters.

Spam filters have some metrics and algorithms to filter emails. After the filtering process, a numerical score is assigned which represents the probability of the message being spam.

Gateway Filters

Large businesses and organizations use Gateway email filters like Barracuda and Mimecast to decide whether to allow the email to go further or not.

Hosted Filters

Hosted Filters like Cloudmark are used in companies which have elaborated their own method to detect spams based on sender reputation metrics and content.

Desktop Filters

Desktop Filters are the tough ones to get through because they are configured by the user. Outlook with the SmartScreen anti-spam filter from Microsoft can be given as an example.

2. You Have A Low Sender Score

a man sending email campaign from his phone and email reach to inbox if his sender score is between 90-100

Sender score is an algorithm that ranks every outgoing mail server’s IP address. It is related to the reputation of the sending IP and sending domain.

Some email metrics determine the Sender Score as the unsubscribes or spam reports.

It shows your sender reputation on a scale of 0 – 100. Having a low sender score (classified as being below 90) leads to rejection by ISPs causing your emails not to reach the inbox folder. Therefore, the higher your sender score is, the higher the possibility of reaching the targeted inbox folder.

3. You Don’t Have a Reputable IP Address

An IP address is a number listed in the domain name system that is used to send email messages on behalf of your domain name. Marketers can use dedicated or shared IP addresses to send emails.

It may be dedicated to a specific sender or used by multiple senders to deliver emails.

Maybe you’ve just gotten a new IP address and didn’t warm it up enough! You should definitely create some reliability before sending too many emails!

Building a reputation is necessary for the quality of your IP! Also, after building a reputation, I recommend maintaining consistent volume levels. Apparently, Mailbox providers tend to filter emails out if they observe spikes.

To see your IP reputation in the virtual world, check the Sender Score tool and find out more.

You can also use Mail-Tester which allows you to easily check if your email address appears spammy to other email servers (Never go below 5 out of 10).

Moreover, if your IP address was used by any other company for spam purposes, your emails are going to be flagged as spam.

If you have a new IP address or have not got a reputable one yet, in order to raise deliverability of your emails, you may use some email providers like MailChimp, Aweber, ActiveCampaign, Infusionsoft, and ConvertKit.

Also if you’re sending emails from multiple IP addresses, that is a big mistake!

4. Your Domain Authentication Matters

Authentication allows the receiving server to confirm the sender’s identity. It is very important to secure your brand, build a good reputation and increase the deliverability of your emails to reach their destination.

More simply, email domain authentication records indicate how healthy the process between your computer and the targeted computer is.

You can check your authentication records with the GlockApps spam testing tool. It allows the receiving server to confirm the sender’s identity. Authentication is very important to secure your brand and build a good reputation.

There are three primary methods of authentication:

1. SPF (Sender Policy Framework): it validates that a message was sent from an IP address that was authorized to send messages on the behalf of the indicated sending domain.

2. DKIM (DomainKeys Identified Mail): it authenticates an email using public-key encryption. It signs a message in a way that is difficult to forge, proving that the message is sent from the indicated sending domain.

3. DMARC (Domain-based Message Authentication, Reporting, and Conformance): it ensures that an email is properly authenticated against established DKIM and SPF standards and that any fraudulent activity that may be coming from legitimate domains is blocked.

5. Your Domain Reputation Matters

You should listen to your audience. For example, if your subscribers can’t get out of your list immediately, they can mark your email as spam.

In this case, domain reputation is very important.

To make the filtering decisions about where the email should go, mailbox providers look at the metric called a domain reputation.

Its reliability is dependent on:

  • Inbox placement rate,
  • Spam placement rate,
  • Complaint rate,
  • “This is not spam” rate and
  • Hard bounce rate.

What is Hard Bounce?

(To see what the rates of your domain are, you can go to: Mailmonitor.)

The worst in those variable rates is high spam complaint rate because it represents your unwanted emails. So, experts say that the ideal complaint rates should be below 0.1%. A complaint rate higher than 0.1% puts a red flag on the sender and will lead to email rejections or blocks if the issue is not fixed.

Additionally, there are some factors affecting domain reputation;

  • How old the domain is (newly registered domains are considered suspicious)
  • How it has been classified on the web (g. business and industry, education, finance, dating, or gambling)

To check your domain reputation in general, you may use a tool called Talos by Cisco.

6. You Weren’t Given Your Customer’s Permission

take the permission of your customers while applying email marketing strategies

Take your customers' permission if you haven't yet. This is the golden rule of email marketing. Believe me, people aren't interested in your special discounts or products if they don’t know you.

If you’re sending emails randomly, you should know that it is unethical and ineffective. There are lots of marketers and business owners that buy an email list, which is a total mistake!

There is nothing you can benefit from an email list that was bought from somewhere else. You should create a target audience and do your best to convert them into loyal customers.

So, you should add someone’s email address if s/he only willingly opts-in to your list.

7. You Don’t Set an Email Sending Frequency

set an email sending frequency in email marketing

Another reason behind you might be flagged as spam is that you might not have an appropriate schedule for your emails. If this is the case for you, please start making one!

Try not to send e-mails to your customers at inconvenient times. Also, as you get to know your audience's taste, you can set an email sending frequency.

If they prefer to get an email from you once a week, you should make that happen.

78% of consumers unsubscribe from emails because brands sent out too many emails. Make your offerings easy for people to take advantage of otherwise you may not be as successful as you want.

You don’t have to send spam to be considered a spammer. If your IP address gets flagged as spam then your reputation is at stake.

Also, an email service provider is an important metric. For example, you may use MailerLite to send your campaigns. That means, your emails are sent through their servers. So, if someone sends spam messages through their service, then your reputation and deliverability can be affected as well.

My advice is to use a reputable email service provider because they prevent such scenarios by means of strict procedures and regulations.

8. You Have Low Engagement Rates

increase email open rate in email marketing

If you have low open rates, your emails are at a higher risk of being flagged as spam.

Remember the first condition of email open rate:

The reader allows images in the email to be displayed in the full view of the email or preview pane.

and the second condition is,

The reader clicks a link in the email.

Open rates are calculated by email service providers. ESPs consider the number of people who open the email and divide it by the number of emails sent that failed to reach the reader.

For example, if you sent out 100 emails, 20 bounced, and 10 were opened, you would have an open rate of 12.5%.

According to MailChimp, the average email open rate of all industries is 20.81%.

Some tips to follow are:

  • Use Engaging Language
  • Pick the Right Time
  • Keep Your Email List Fresh
  • Segment Your Email List

9. Your Email List is not Fresh


1 in 1000 people will mistype their email address, and you will never hear from them again. That equates to over one million dollars lost in return on investment.

To prevent wrong, extra, missing or swapped letters in your customers' email addresses, you can use a code inventory.

  • If the function finds something that looks like a typo, it will return a suggestion
  • If the function doesn’t find a typo, it returns an empty string

Actually, it is a very simple process! A typical email validation flow looks like this:

email validation flow in email marketing

What is Email Verification?

In the end, you don't just lose a customer, but also your emails are also at risk of being flagged as spam for those who actively engage in your email marketing campaigns.

Additionally, emails can be inactive for other reasons even if they have given you their correct emails;

  • They may not be using their emails in your list anymore, or
  • They may quit their jobs so their business mail addresses become invalid.

Therefore, email list cleaning is something you should definitely do for a high-quality email list. If you don’t do that regularly, this could be the reason for your problems!

You should update your email list and remove inactive subscribers who have not engaged in the past 6 months or more. Also, you should try re-engaging them. Ask them if they’d like to update their preferences and information. This way, you can clean up your list. By eliminating the bad data, you’ll achieve the goals you have eventually.

If you need some advice on and want to see the comparison of some email list cleaning service, click the link below:

Best Email List Cleaning Services

10. There is no Unsubscribe Link or Opt-out Link

In order to avoid spam complaints, you should use a double opt-in form. This way, you can collect real data and provide your valuable services and offers to people who actually want them!

Also, don’t forget to send a confirmation email to all new subscribers in order to confirm their email address and establish a subscribing agreement.

There are some ready-to-use email templates provided by Sendloop, which already consist of opt-out links.

To easily manage your opt-out link requests, you may use a tool called GroupMail Subscriber Add-On which provides a service to automatically exclude recipient opts-out.

What is opt-out?

11. You Have Incorrect Sender Information

If you don’t provide accurate information about your routing information as well as the domain name and email address, this might be a cause of concern!

You should identify yourself and your business with accurate sender information.

12. You Didn't Include Your Physical Location Address

According to the Federal Trade Commission (FTC), including a valid, physical postal address is necessary. Companies and marketers should be transparent and traceable.

In this case, you should include your street address, a post office box that you’ve registered with the U.S. Postal Service or a private mailbox you’ve registered with a commercial mail receiving agency established under Postal Service regulations.

13. Your Subject Line is Misleading

35% of email recipients open an email based on the subject line alone. Don’t use more than 50 characters in your subject lines. Also creating a compelling and eye-catching subject line will be helpful to increase email open rates. Don’t forget to trigger your customers with an immediate call to action.

Also, you may generate curiosity with compelling questions and personalized email subject lines! Finally, don’t forget to A/B test your email subject lines to understand which ones best fit your business & audience!

An attractive email subject line example is:

Email subject line example by stripo

For detailed information about email subject lines, please check the link below:

50 Best Practices of Abandoned Cart Subject Lines

14. You Used Spam Trigger Words

If you’re ending up in a subscriber’s spam folder, you might be using spammy terms! Most ESPs have identified some common words in spam emails. You can check spam trigger words based on your industry and avoid using them! Here you can find a detailed spammy word list, check it out for more details.

The Ultimate List of Email SPAM Trigger Words

15. You Have Spelling Issues & Grammatical Errors

Grammar mistakes and spelling errors in spam emails

There are a lot of spammers who are not English native speakers. So, when you analyze their email, you will find various grammatical errors.

In order to block those kinds of emails, spam filters detect such errors. Also, when you regard email marketing as something serious, you will be more careful with your tone of voice and spelling.

Most importantly, in B2B communication, it is essential to appear professional in the eyes of your audience.

In this case, I recommend that you use Grammarly, but for the best results, you should proofread your emails before hitting the "Send" button!

13. Audience Wants HTML Format Emails

Maybe your segmented audience prefers to get emails in HTML format and your emails don't follow that format!

In that case, you should

  • Make sure that your HTML code is simple and clean. Stay away from complexity.
  • Never send image-only emails with no text and of course, compress them for the ideal size.
  • Use fonts that work across platforms, unknown fonts don’t work everywhere.
  • Make sure that your emails are mobile responsive.

How to Avoid Emails Going to Spam Summarized

1. Be careful about your sender reputation (low: classified as being below 90). Don’t forget, the higher your sender score is the higher the possibility of reaching the targeted inbox folder.

2. You can authenticate your domain with the Zoho Campaign tool.

3. You need to have a good domain and IP reputation

To keep the rates mentioned above ideal, you should:

  • Have a list that is free of inactive email addresses,
  • Create relevant contents to reduce complaints,
  • Keep your mail volume and frequency consistent,
  • Set appropriate expectations for your subscribers when sending a welcome email, and
  • Create email campaigns that enable your audience to engage in the matter.

Moreover, after you check your domain and IP reputation via Talos, you will be shown a reputation as Good, Neutral (there is something you can improve) or Poor (most of your emails won’t get to their destination).

  • If the result is Poor, the best thing to do is set up a new email and work on a good reputation by warming it up.
  • If the result is Neutral, you can try to improve it by optimizing your sending workflow (Try to make the email flow more steady and fluent).

4. Take your customers’ permission to receive emails from you.

5. Set an email sending frequency based on your customers’ wants and needs.

6. Increase your open rates by:

  • Using engaging language (both in the subject and content)
  • Picking the right time for your customers
  • Keeping your email list fresh and full of active emails
  • Segmenting your email list based on needs and wants of the target audience

7. You should use a double opt-in form in order to collect real data and provide your value to people who want them.

8. You must be careful about writing sender information accurately. It should contain an appropriate physical location address, a very effective and related subject line, and no spammy words in the content.

9. You must be very elaborate when writing your emails in terms of grammar and spelling of content because these types of mistakes are neither spam filter nor customer friendly.

10. You ought to make sure that your HTML code is simple and clean. Stay away from complexity.

11. Make sure that your emails are mobile responsive.

So, in this article, I tried to tackle some common reasons and practical solutions for your email marketing benefits!

Remember, the golden rule in email marketing is to make people open your email. That is why you need to reach the inbox and pass all spam filters.

Why Do Emails Go to Spam Instead of Inbox Infographic

Why Emails Go to Spam Instead of Inbox & What to Do They Don’t Anymore infographic

We like sharing our knowledge with our visitors! You are very welcome to use our infographic on your website for presenting excellent information about how to prevent emails going to the spam folder instead of your subscribers' inbox.

If you could share some techniques that you have used to prevent this situation from occurring, I’d love to hear them!

You can visit our detailed guide to learn email marketing from scratch.

Thank you for your time!

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