How to Make Sure Your Emails Land in the Inbox (Not in SPAM)

Samuel Chenard
by Samuel Chenard

Every day, approximately 350 billion emails are sent and received. Of these, more than 45% end up in spam. This leads to significant losses for businesses, as marketing emails don't reach their subscribers, transactional emails fail to inform users, and colleagues struggle to communicate effectively.

Magnification glass looking at customer base

Email deliverability is somewhat of a black box, much like SEO. The rules are constantly changing and are not clearly disclosed by major Email Service Providers (ESPs) like Google, Apple, Microsoft, and others.

Sometimes these rules are disclosed, as seen recently with the announcement from Google and Yahoo about the enforcement of new security protocols starting in February, but they are often kept unclear.

The good news is, despite the uncertainty, you can greatly improve your email deliverability. If you are worried your messages are getting lost in an email black hole, keep on reading as we’ll delve deeper to understand the main reasons why emails end up in spam, and how to prevent this.

What is Email Deliverability?

Before we dive into why your emails end up going into spam, let’s first explore a subtle yet so important distinction:

It’s not because your emails show as delivered in the tools you are using (also known as bounce/delivery rate) that they are actually reaching your recipient’s inbox.

Email deliverability is the odds that your email makes it to your customer's inbox and not in their spam.

Why Do Emails End Up in Spam?

There are several reasons why your emails might end up trigger the spam filters. It can be a long story, but it can be simplified into four pillars:

  1. List Management: Sending emails to unsubscribed addresses is a major red flag. Your list should be built organically with permission-based opt-ins. Plus, if you’re still sending emails to old and inactive accounts that end up bouncing, it can negatively impact your reputation.
  2. Content & Engagement: Using excessive exclamation points, ALL CAPS, misleading subject lines, or irrelevant keywords can trigger spam filters and route your email to no man's land.
  3. DNS Configuration: Not implementing email authentication protocols like SPF, DKIM, and DMARC is another redflag for ESPs. These act like digital IDs by verifying your legitimacy and preventing impersonation by spammers.
  4. Monitoring & Optimization: Not regularly keeping track your email deliverability metrics like spam rates, open rates, and click-through rates is another no go. This data can help you identifying areas where you could improve, like content adjustments, list cleaning, or technical optimizations.

By avoiding these red flags, your emails will be able to land in the inbox of your recipients more easily.

Best Ways to Prevent Emails From Going to Spam

List Management


The method you use to collect emails and build your subscriber list has a significant impact. If you employ a deceptive approach to obtain emails and then send these users unsolicited messages, it's likely that these recipients will be displeased with your unexpected emails. The more dissatisfied they are, the more likely they are to mark you as spam.

Ensure you use an opt-in form that clearly communicates to users that they will receive content from you by agreeing and checking a box or a similar mechanism. Be clear, don’t try to be sneaky.


Make it easy for people to unsubscribe. Don’t try to hide the link grey on white at the bottom of your email template. People who are unable to unsubscribe are actually people who will flag your email as spam and damage your reputation.

To encourage organizations to have the best practices on this, Google and Yahoo just made it mandatory to have an Unsubscribe button directly in the header of your email. Here’s how it looks:

Example from Jason Cohen’s AsmartBear newsletter, which Palisade helped get compliant.
Example from Jason Cohen’s AsmartBear newsletter, which Palisade helped get compliant.

Cleaning Your Lists

Deprecated Emails

You can use third-party tools to remove emails that have been deactivated or accounts that have been banned. Those create hard bounces and hard bounces are bad for your reputation.

We personally like Neverbounce.

Sunset Policy

If a certain group of subscribers has not opened a single email in the last six months, you might want to send them an email asking if they're still interested. Ultimately, emails that are not interacted with are likely to be flagged as spam.

This is not beneficial for your sender's reputation, and it's a poor final point of contact with your brand for the user. We recommend being kind and warm about it. Let them sail into the sunset if that's their wish!


It's no secret that the type of content you send to your recipient is one of the most important aspects of a successful email campaign. People's time is extremely valuable, so ensure that when you ask for their time to read your content, your content is of top quality and feels genuine.

Here are the most important questions to ask yourself before hitting send:

  • Relevant and exciting content?
  • Is it well-written and to the point?
  • Is it well-designed and fun to look at?
  • Is it made for my audience?
  • Does it use any words that could trigger a spam filter?
  • Would I like to receive this email if I were the reader?

Infrastructure Configuration

Authenticating and securing your emails is a crucial step in ensuring your emails reach the inbox. It's often overlooked by many companies, yet it's one of the easiest ways to improve deliverability.

There's a complex relationship between security and compliance. ESPs aim to reduce spam, scams, and phishing attempts. To support this, they favor domains that have well-configured security and authentication protocols on their domain's DNS.

Although this part can be quite tricky to understand and configure, it's incredibly valuable. It can make the difference between a +39% open rate and a +34% purchase likelihood. Isn't that amazing?

So, What Are Those Authentication and Security Protocols?

Understanding DNS

DNS is like the address book of the internet. Computers use DNS to look up domain names to find the corresponding IP addresses needed to connect to websites, servers, and other internet resources.

That’s also where email service providers like Google, Apple, and Microsoft are instructed on how your emails are secured and authenticated:

  • Who is authorized to send emails on behalf of your domain (SPF)?
  • What is the signature they should look for to ensure the content is authentic (DKIM)?
  • Is your domain protected by a policy? (DMARC)
  • Is your sender’s identity verified? (BIMI)

Let's dive into each one of these one by one.

Authorized Senders List - (SPF Record)

SPF Records are like a guest list for sending emails. An SPF record is a line of text that specifies which domains or IP addresses are permitted to send emails on behalf of your domain. It resides in your DNS manager, under TXT records.

Here’s an example of an SPF record:

v=spf1 ip4: ip6:2001:db8::/32 ~all

If an email from your domain is sent to a recipient server without your domain's permission, it could potentially decrease the email's deliverability.

A quick tip: To analyze whether your DNS is configured properly and if your email has a high likelihood of reaching the inbox, you can use Palisade’s free Email Deliverability Score tool. This tool audits your DNS configuration and provides suggestions for improvement.

Digital Signature - (DKIM Records)

DKIM records add a digital signature to your emails that proves they are authentic when they get to the recipient server. It's like the signature on the back of your credit card.

Each third-party service you are using with your domain typically needs its own DKIM key and record.

Here’s an example of an DKIM record:

v=DKIM1; k=rsa; p=MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAgAS4QZzH+/iM5ilpxexFK7uVnX5OasDMW61p7IvUjM+488QnpLqDTlsvGdJtG/oHgwRpXcNSxKKhtX3R4zg0MoSdLJYTEMiirr8UdeuGng/ZKM2XtLa+qGve6kp3H5NBx2uYHVj+E0WANeRT3bK5sMVRTYSAywN/m9ugX5T5PkbvJ2HRTmrX00ov4/VoVFSbfHZzaA/FDX/hyFnWEiOb1JihArP2+cMs+CYgIi7u8t+p0FqR/37kuEh5PLxOct/fnhqjn35XPn8C1s2fAC5J2WZjmmC5QM2qYV90isu03jeCI7Vap9ocKj5P+qJAlooYNujICd84ZmcHeA2UJqj22QIDAQAB

Defended Domain - (DMARC)

Protects your domain from people who try to send fake emails (phishing, spam) on your behalf.

The DMARC policy is central to your email deliverability and security. It tells the recipient servers what to do if the emails they receive from you are not authenticated properly in your SPF or DKIM (often referred to as alignment).

Here’s an example of a DMARC record:

v=DMARC1; p=none;;; fo=1;

Recently Google and Yahoo have started enforcing DMARC policies for all email senders.

Brand Display and Verified Checkmark - (BIMI)

BIMI is the new hot kid on the block. It was just adopted by Google, Apple, Yahoo, and most major ESPs (looking at you Outlook) this past May 2023.

It is now required to verify your identity via email, display your logo in the inbox, and get a verified checkmark in the inbox. You can see it being slowly rolled out by major companies like LinkedIn and Google:

Verified checkmark in the inbox exemple with LinkedIn

Here’s an example of a DMARC record:



Monitoring your sender reputation is a significant component of ensuring your email deliverability remains high. Your sender reputation is much like a person's reputation. It takes time to build and is easy to damage.

Unfortunately, there is no "one tool to rule them all" for monitoring. However, there are tools available that can provide some insight into the status of your deliverability.

Domain Reputation, IP Reputation and Spam Rates

One of the best tools out there, even if it only monitors your reputation from Google's perspective, is Google Postmasters.

It allows you to get key data points on your sender reputation from three key angles:

  • Domain Reputation: How your domain is viewed by Google holistically. All emails coming from all apps combine into one reputation.
  • IP Reputation: How the third-party app's IP reputation influences your sender's reputation.
  • Spam Rate: The number of users reporting your emails as spam.

Wrapping Up

Email deliverability is not set and forget, it’s a constant piece of work but oh so worth it.

Many companies spend a significant amount of time A/B testing their funnels and producing content. However, they often overlook the crucial step of ensuring their emails reach their customers' inboxes. If your users aren't seeing your content, what's the point of investing so much in creating it?

We understand, it's not easy. List management best practices are always changing. Content engagement follows the latest trends and designs. DNS compliance is constantly evolving. Reputation Monitoring is sensitive.

After reading this article, we hope that you've gained a better understanding of the basics of email deliverability (and the difference between your emails being delivered), and that you will place more importance on it.

Samuel Chenard

Sam is a repeat founder who built and sold multiple companies. With his previous startups revenues relying heavily on email and email deliverability, Sam and the Palisade team committed to creating the top automated email delivery and reporting platform.
Follow me on LinkedIn and Twitter