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Landing in the Inbox: 5 Ways to Improve Email Deliverability

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If you’re like most marketers, you probably rely on email marketing as a significant part of your overall strategy.

After all, ROI for email marketing is higher than any other digital marketing channel.

But how do you know that your emails are actually landing in your prospects’ inboxes?

Fewer emails reach their intended recipients than you might think.

According to data from ReturnPath, just under 1 out of 5 emails never makes it to the recipient’s inbox. Increasing your email deliverability rate is a vital part of creating a winning email marketing strategy for your business.

Why waste your time creating stellar email content if you aren't confident people will actually see it?

This guide provides an overview of email deliverability – from what it is, the factors that influence your emails' success, and best practices to improve your email deliverability rate.  

Let's dive in!


What is Email Deliverability?

What is the definition of email deliverability? First, let’s discuss the differences between “email delivery” and “email deliverability”—two very similar terms.

While “email delivery” refers to your email's ability to reach a recipient at all, “email deliverability” determines if your email will land in the inbox or head straight to spam. The percentage of emails that arrive in the inbox itself is known as the email deliverability rate or inbox rate.

So what is an optimal email deliverability rate?

Well, in an ideal world, all of your emails would arrive in the inbox. But since most gateway servers don’t provide metrics to senders about whether or not emails are sent to spam folders, getting a specific number is difficult.

However, there are plenty of email marketing best practices to put in place to increase the likelihood that your emails will land in the inbox.


What Affects Email Deliverability?

There are a few tell-tale signs that your email deliverability could use some TLC. The major factors in email deliverability include sender score, message content, list quality, and spam reports—all of which are interconnected.


Sender Score or Email Sender Reputation

How much can a mailbox provider trust your IP address and sending domain?

The term for this is sender reputation or sender score. Sender score metrics are determined based on factors like how many spam complaints you have, the quality of your mailing list, and if your IP address or domain appears on any industry blacklists.

The better the sender score, the more likely you are to have a high deliverability rate.


Message Content

Message content refers to the text, images, and formatting of your email. Low-quality message content can be a ding on your sender score and decrease your deliverability rate.

For example, do you use subject lines that might be considered “clickbait”—and annoy recipients? Does the message within the email match what your audience is expecting? How do the design and format of the email help to convey your messaging?

Poor formatting could mean funky capitalization, inconsistent fonts, or general illegibility. Looking for some examples of what not to do in your email marketing?

Here's a list of the ten worst marketing emails of all time.


Poor List Quality

For some businesses, it can be tempting to send mass emails to anyone who has ever subscribed to a mailing list (and even some who didn't). However, this approach will hurt list quality and lead to poor email deliverability in the long run.

Some ways to tell that your list might be poor quality include spam complaints and a high percentage of inactive users.

This is why it's crucial to segment your audience before sending an email to ensure that only relevant content is delivered to them and review your mailing list at regular intervals and purge inactive users.

Remember, you want your emails to go to the recipients most likely to open them.

Fundamental to maintaining a quality mailing list is to ensure that you're adhering to relevant communications legislation, such as CAN-SPAM in the U.S. and GDPR in the European Union.

While each law's specifics vary, both require that recipients have an easy way to opt-out of future communication from your company.

GDPR also requires a double opt-in—which is a good practice to adopt, no matter your location.


Spam Reports

Spam reports, also known as "abuse reports," harm email deliverability, too.

This happens when a recipient marks your email as "spam" when receiving it in their inbox.  

If you receive too many spam reports, mailbox providers may blacklist your domain or IP address.

Aim for a spam rate that is less than 0.08%.



Have you ever signed up for a retailer's email list, opened their welcome email, and deleted everything else they sent you afterward? This scenario is commonly known as graymail.

Graymail isn’t spam, per se, since the recipient opted in to receiving emails. However, recipients don't actually want to receive those emails, so they don’t open them. ISPs recognize user engagement patterns and will eventually start filtering these messages out as spam.

Graymail might indicate that your mailing list could use a refresh, or your targeting needs to be more precise. It’s also possible that you should send fewer, but more enriching emails.


Email Deliverability Tools

At this point, you might be thinking, “How do I check if an email I'm sending is going to spam?"

Fortunately, there are a bunch of email deliverability tools you can use for testing. Some tools, such as Mail-tester.com, GlockApps, and SendForensics, allow you to send a copy of your email to a specific email address for analysis of the quality of the content—as well as its likelihood of ending up in the inbox or spam folders.

Spamcheck by Postmark offers the same email deliverability testing capabilities but asks you to paste your email’s HTML code into a dialog box instead.

Another useful resource is senderscore.org, which analyzes sender reputation based on your IP address. 

Hearst Bay Area also offers a number of tools to help your emails get in front of the right audience. Check out our email marketing services for a full rundown on how we can help. 


Download email marketing program brochure A


5 Email Deliverability Best Practices to Follow

There are plenty of tactics you can use to improve email deliverability, making sure that all of your awesome content is making it to your audiences. Incorporate these best practices into all of your future campaigns – let's jump in! 


1. Send high-quality content

First and foremost, create emails that your recipients will want to read! Start with an engaging subject line to entice them to open the email. Make sure any headers, images, and text within the email reinforce the subject line so that subscribers feel prepared for what they are about to read. The formatting should also be clean and consistent, with a clear call-to-action

Personalization also goes a long way toward making emails more likely to be perceived as relevant to subscribers. Most email platforms such as Mailchimp have merge tag features so that you can auto-populate the recipient’s name into the email as a salutation or part of the subject line.

You can capture first and last name information in your sign-up form for your mailing list.


2. Segment your audience

As previously stated, most of the time, you should not be sending out emails to your entire subscriber list. Instead, target your emails more accurately based on audience interest, location, or how they've engaged with your emails in the past.

For example, If you're a clothing retailer, an individual without children probably doesn't want to receive an email all about your new line of kids' clothes. Similarly, if you're an educational institution that offers adult classes in a wide range of subjects, you'll probably want to segment your list based on courses' subject areas (like coding vs. art vs. accounting).

You can collect information about interests in the user sign-up form. You might also ask users to opt into specific newsletters.

Another targeting method is to send your emails to users who are most likely to open or engage.

Maybe you'll only send an email to new users and those who have opened an email from you in the past three months.

Or perhaps you want to highlight a specific product, and you'll only send an email to recipients who have clicked on an email link to view that product before.

Or if you’re targeting a specific city or neighborhood, try segmenting by location.

Here is an example of targeting criteria for recently engaged users in the San Francisco area:

Email Deliverability Targeting Example


3. Manage your lists regularly

Remember: just because you have 10,000 email subscribers doesn't mean all of them are still interested in your business or represent high-quality leads. Cleaning your lists at regular intervals is more likely to improve your email sender reputation and ultimately help you land in the inbox.

In addition to removing subscribers who are no longer interested in your emails, develop other marketing campaigns that encourage new subscribers to join your mailing list. Try some of these ways to grow a healthy email subscriber list.


4. Make it easy to unsubscribe

You can partially avoid the graymail problem by including a clear unsubscribe link in each email, in a consistent location.

For example, most email users are used to seeing "unsubscribe" at the bottom of the emails they receive. You can also send out an automated “re-engagement” campaign at regular intervals, such as if a subscriber hasn’t opened an email from you in six months, to ask if they are still interested in your emails or if they would like to unsubscribe. This is another handy way to keep your mailing list clean!


5. Find the right frequency 

You don’t want your subscribers to feel burned out by your promotional emails—or for your emails to be unintentionally turned into graymail. But at the same time, you don't want to lose valuable opportunities for communicating with your audience.

That's why it's important to test out the frequency of your emails to find what works best for your audience. You might start with one email per week (not counting a welcome series or necessary operational emails such as receipts or confirmations) and then adjust based on engagement metrics.

Having a good email deliverability rate requires continuously monitoring things like sender reputation, email lists, and quality message content. In addition to monitoring your company's email metrics, keep up with industry trends so that you always have your finger on the pulse.

Email is still a crucial channel for most businesses, so it’s worth the extra time and effort to get it right!


Landing in the Inbox for Article


Landing in the Inbox: Key Takeaways

Improving your email deliverability rate can go a long way in optimizing an already fruitful marketing technique. Here are some key takeaways to keep in mind:

  • Email deliverability refers to the likelihood that your email will land in the recipient's inbox rather than the spam folder.

  • Many factors affect email deliverability, including list quality, spam reports, message content, and sender reputation.

  • Use email marketing best practices to improve email deliverability, especially when targeting your audience and providing high-quality content. Make sure you scrub your mailing list at regular intervals too.

  • Always follow relevant legislation, such as CAN-SPAM in the U.S. and GDPR in the European Union.