Everything You Need to Know About Email Deliverability

increase email deliverability

Your email marketing campaigns are as good as your email deliverability rate. However, email deliverability is a tough nut to crack. In this blog, we will share with you everything that you need to know about email deliverability to send high-impact campaigns.

Table of Contents

What is Email Deliverability?

Email deliverability is the ability to deliver emails to your subscribers' inboxes. Marketers use deliverability metrics to measure the likelihood of email campaigns reaching subscribers' inboxes and not the spam folders.

EmailToolTester claims that the average email deliverability rate for commercial emails landing in the Inbox is 79.6%. The rest is sent straight to the spam folder or blocked by the mailbox provider.

For future email campaigns, keep in mind these metrics and their baselines when you track your overall email deliverability:

  • 95% and higher is considered a good delivery rate on behalf of an email service provider.

  • The bounce rate shouldn't be higher than 3%.

  • It would be best if you weren't ringing the alarm bells in terms of the SPAM rate as long as it doesn't exceed 0.08%. (Source)

Most importantly, your email deliverability depends on the email marketing platform that you use for sending emails. Every forum has different delivery rates. A reasonable email deliverability rate should be over 80% to 90% to enjoy the success metrics.

Difference between Email Delivery and Email Deliverability

There are a lot of misconceptions about Email delivery and deliverability which are two different concepts. As an email begins its journey from the sender's server to the recipient's Inbox, delivery and deliverability are two separate chronological events happening one after the other.

Email Delivery

It tells you whether the email sent by you is received or not by the servers of your subscribers' inbox providers. If there is no bounce(inability to deliver to the servers), then the email count is taken as delivered. The delivery rate is the total number of emails delivered for the number of emails sent by you.

Email Deliverability

Mail service providers decide where your emails should land - inbox or spam. Email deliverability is the landing of an email in the Inbox. The place of delivery differs based on the domain reputation, authentication, and domain set up. If there is an issue with any of these factors, your deliverability rate will face a massive hit. There are chances for deliverability issues, even with a stellar delivery rate.

Why is email deliverability important?

In sales, the first step towards a successful pitch for a traveling salesman is to gain entry into the user’s house. Similarly, in email marketing, the first step towards getting ROI from email campaigns is to land in the end user’s inbox.

1. Your email marketing success depends on successful deliverability

Email deliverability is the foundation for email marketing. As a primary step, marketers pay an ESP to send emails for them. Still, it's the marketer's responsibility to manage the email program and subscribers list in the right way to ensure emails are landing in the subscriber's inbox or spam folder.

Marketers put so much effort and time into writing a perfect email copy and creating campaigns. Their effort goes in vain when the target audience does not open the sent emails because of poor deliverability.

2. It can help you to be a winner in the inbox competition

Every business fights for its place in the consumer or client's inbox and as a result, the email platform is very competitive. Everyone wants their emails to be read by leads and prospects and be far away from the spam folder. Good email deliverability helps you to build a healthy relationship with the subscribers, which won't affect your email conversions and help you to stay ahead of the competition. Since reaching a consumer's inbox is an important growth metric then deliverability is a superpower for businesses.

3. It helps you to study and understand user behavior

Email deliverability helps in tracking the number of users opening your email, what time they have opened it, the number of active subscribers, etc. These insights are used to enhance user engagement and gather leads for better and improved email deliverability

Challenges in measuring email deliverability rate

Measuring email deliverability rate is challenging at present. Some try to measure email deliverability approximately by accounting where the emails are landing and infer whether the ISP has accepted it. But these do not represent the actual email deliverability rate.

Email servers do not return spam counts

The number of your emails that end up in your recipient's spam folder is one of the crucial aspects that you might skip while measuring. It's because the messages that are sent to your email servers don't return this information. You may receive a message like, the mailbox is full, or the email address you try to reach is inactive, but you will not be able to identify the right reasons why your message is not delivered.

No accurate email landing information

You will also not be able to identify whether the email you send is landing in the spam folder, Inbox, promotional, or other folders. The reason is that the filtration of emails to the recipient's mailbox varies based on different factors, including how they interact with the previous communication. The system may send the email to the Inbox immediately. Still, the email gets to the spam folders in case of higher traps, bounces, and complaints, so it's a bit tricky to measure email deliverability.

What are the standard methods of testing deliverability?

We have seen that measuring or testing email deliverability is critical. However, there are some ways to measure it. Some of these email deliverability tests are as follows:

Seed list testing

A seed test is essential before running any of the email deliverability tests. A seed list will have validated and whitelisted email ids where you will send the emails before sending them to your recipients to check whether your emails are landing in the Inbox. It enables you to test your email across different devices and email clients.

Content filtering testing

Filtering your email messages based on specific content filters like MessageLabs, Cloudmark is called content filter testing. Email screening for different malware, spam, and other malicious or undesirable content is done by scanning the email's subject line and then forwarded via the content filtering system. Whenever an email doesn't pass the content filter test, goes to the recipient's junk folder. The chances are that the message will be sent back to the sender with a message "undeliverable" in some cases.

Domain and IP blacklist testing

This testing helps in checking whether your domain and IP address is on the anti-spam database. The testing also includes checking domain and IP addresses and different blacklist providers to ensure your email deliverability is not affected. Use tools like mxtoolbox.com and ultratools.com to instantly check if your domain is blacklisted.

Authentication testing

This test verifies whether your email is passing through DKIM, DMARC, and SPF checks. Both DKIM and SPF technologies are email authentication technologies used to manage inbound spam. This also checks if your IP address and the domain are on an anti-spam database. That involves checking IP addresses and domains across various blacklist providers to ensure your email lands in the recipient's inbox.

How to detect a change in your deliverability using engagement signals?

While measuring the exact deliverability might be tricky, there are some signs that you can watch to understand the trend of your deliverability rate and take contingent actions in case it dips. Some of these signals you should monitor are as follows:

When there is low email open and engagement rates

Low open rates in email deliverability terms are signals to ISPs that indicate that your recipients are not engaging with your content. The lack of engagement can even make your email domains get blacklisted.

You can read more about decreasing bounce rate in this guide.

When the open rates drop for a specific mailbox provider

A dip analyzed in your mailbox provider's engagement metrics gives you a chance to be added to the blacklist or get blocked. Another vital sign identified for spam folder placement is when you have significantly lower open rates in the range of 1 to 2%. Deliverability professionals can easily read engagement rates and identify you are in trouble or moving in the wrong direction.

When the bounce rate is above 3 to 5%

Soft bouncing is normal for large senders due to the small mailbox provider's deferrals. They accept only certain mails at a specific time when you cross higher than 3% soft bounce rate that too at Outlook, Gmail, and other top providers, there is a high chance of getting blocked for the reputation issue.

You can read more about improving open rates in this guide.

When the email complaint rates cross 0.2%

When the email complaint rate crosses 0.2%, it indicates a problem. The metrics can move to the lower side as smaller mailbox providers do not provide any feedback loop, which won't redirect any complaints back. Therefore the overall complaints can be misleading. The campaign and recipient domain need to monitor the complaints carefully.

What factors affect email deliverability

Multiple factors determine if an email gets blocked, delivered, or even filtered into junk or spam folders. Some of them include the following:

IP Addresses

The numerical identifier of the server (sender) is known as the Internet Protocol address. Every device connected to a computer network holds an IP address. The server's reputation can be analyzed based on IP address based on factors like send volume, user interaction, send frequency, and the percentages of undeliverable emails or bounces.

The IP Reputation can be checked on different services, namely the email deliverability service, sender score from Return-path, and more. Most of the organizations make use of other email service providers to send their marketing emails. Shared IP and Dedicated IP are the two different types of IP addresses.

Shared IP: More than one brand or company is using the same IP address to send emails.

Dedicated IP: The brand or company has its unique IP address which is not shared with any other companies or brands.

Running multiple types of campaigns from a single domain

It's always good to use a separate domain for sending transactional emails like shipment notifications, product updates, or confirmation emails. The reason is that if your domain becomes compromised or your marketing emails are flagged as spam, your transaction emails will remain unaffected as they are sent from a different domain. Use tools like mxtoolbox.com or any other blacklist checkers to ensure your transactional email domain is not flagged as spam as that would lead to blacklisting.

The behavior of recipients

Deliverability algorithms evaluate the recipient's actions. In case an individual is not opening your email and deleting them without opening it, then the ISP will send the email automatically to the junk or spam folder. Unsubscribers and excessive complaints can lead to issues in the future.

The best option is to use different strategies that make use of clicks and opens. You can use relevant and engaging subject lines, delete the subscribers who are not active on your wishlist, adjust the frequency as required by the subscribers, and make sure the FROM address and subject lines are not misleading in your email.

Content and subject line

Email body content and subject mails can trip spam filters, and therefore you will have negative impacts. Make sure you have a mix of both text and images. The ideal ratio is to have 60% text and 40% image. Ensure you are not using random punctuations or capitalization. It's best to perform a spam check even if you have a small doubt, include the sender's physical mailing address and unsubscribe link, and use appropriately formatted and clean HTML code.

How to improve email deliverability?

The higher the email deliverability, the higher are the chances of the conversion rate and the higher the chances of ROI. That is why it's crucial to improve your email deliverability metrics. There are different ways in which you can improve your deliverability metrics.

Check out our article on how to increase email deliverability to read through the different ways and implement them right away before it’s too late.

If you want to create and send actionable emails that power unique email experiences, check out Mailmodo. With Mailmodo, you'll get higher email conversion rates and an app-like email experience for your users.

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