Email Marketing Deliverability—Best Practices to Reach the Primary Inbox

illustration of a computer screen with various mail icons
Published on
Jan 19, 2024
Written by
Kurt Diver
Kurt is Director of Email Deliverability at Attentive. Outside of work, he loves to travel with his family and tackle home improvement projects. He calls Colorado home.
Thank you! You've been subscribed.
Oops! Something went wrong while submitting the form.

Here’s how to make sure your emails don’t get lost in cyberspace.

There's a lot that goes into running a successful email marketing program. Building an engaged list of subscribers is one essential component. Crafting compelling, personalized campaigns is another. Staying up-to-date on and adhering to the latest requirements for email senders is a must.

But to get the most out of your efforts, your emails first need to reach their intended destination: your subscribers' primary inbox.

Your email deliverability depends on many factors, and there are some actionable steps you can take to improve it. Read on to learn what email deliverability is, the new email sender rules from Google and Yahoo, and common deliverability issues, plus best practices for avoiding them.

What is email marketing deliverability?

Email deliverability refers to the ability of a marketing email to reach your subscribers’ inbox without being blocked or marked as spam. In other words, it’s a holistic view of all the factors that could impact whether or not an email ultimately gets delivered.

This includes open rates, click rates, spam complaint rates, bounce rates, and unsubscribe rates, broken out by mailbox provider (e.g., Google, Yahoo/AOL, Microsoft). Monitoring all of these metrics together helps you understand if the messages you’re sending are making it to the primary inbox.

What is email delivery vs. deliverability?

Email delivery is when an email message is accepted by a mailbox provider. 

There’s a misconception that “delivered” means the message was put into the subscriber's primary inbox, but it really just means that (1) the recipient’s email address was technically correct and (2) the mailbox provider accepted the email.

Depending on a mailbox provider's system demand or anti-spam message algorithm, a message will be accepted and delivered immediately or queued for future delivery. It could also end up in a tabbed folder or in the junk folder. 

Bottom line: If you focus on improving your email marketing deliverability, you can increase the likelihood of your emails landing in your subscribers' primary inbox. 

Why is email deliverability important?

You've put a lot of time and energy into building a quality subscriber list and refining your strategy to engage those subscribers effectively. But if your emails don't reach their intended destination, your efforts won't be as successful. 

When you have low email deliverability rates, your subscribers can't click and convert from your emails, which can impact your program's overall ROI.

New email sender requirements for 2024

Email service providers are constantly updating their sender requirements to make sure that only legitimate and trusted senders can deliver emails in high volumes. These rules are ever-evolving to help create safer, less spam-filled inboxes. 

Google and Yahoo recently announced new requirements for senders who send more than 5,000 messages per day. The new rules, which go into effect starting February 1, 2024, aim to enhance email authentication, simplify the unsubscribe process, and prevent unwanted emails from reaching consumers. 

Here's what you need to know (and do) to make sure your email marketing deliverability isn't impacted by these changes: 

Set up DMARC email authentication for your sending domain

Verifying the authenticity of the sender is crucial for maintaining email security. Mailbox providers rely on authentication protocols like SPF (Sender Policy Framework), DKIM (DomainKeys Identified Mail), and DMARC (Domain-based Message Authentication, Reporting, and Conformance) to verify the legitimacy of sender domains.

Failing these checks can lead to your emails being marked as spam or not being delivered at all. That’s why it’s long been considered ‌best practice to configure these protocols. However, many high-volume senders fail to properly secure and configure their systems, making it easy for spam to go undetected among legitimate emails. So to address this issue, Google and Yahoo have now made it mandatory for large senders to have a DMARC policy in place.

DMARC is like an extra layer of security for email authentication. It's all about making sure your emails reach their intended recipients and keeping your communication safe. 

With DMARC, senders can indicate whether their emails are protected by SPF, DKIM, or both (at least one of these methods is required to pass DMARC authentication). It also lets you set rules for receiving servers when an email fails SPF or DKIM authentication checks, such as sending those emails to spam folders or rejecting them altogether. 

If you don't already have a DMARC policy in place, you must configure one on your root domain.

Attentive has partnered with Red Sift, a leading DMARC and security vendor, to help our customers meet the minimum requirements set by Google and Yahoo.

Always send emails “from” your own domain 

Google and Yahoo will now require senders to use their own domain in the “From” address of an email. The domain in the “From” address must also match the domain in your SPF or DKIM record. 

This requirement is part of the stricter authentication measures being implemented to enhance email security. It’s a necessary change considering many senders fail to adhere to this practice, resulting in a lack of proper authentication for their domains. When the “From” domain is inconsistent, mailbox providers struggle to determine the legitimacy of these emails and establish the sender's reputation. 

When you onboard your email program with Attentive, we provide you with DNS records to make meeting this requirement easier. These records enable us to authenticate your emails sent through our platform using DKIM and SPF, which, in turn, ensures that your emails are recognized as legitimate and trustworthy by mailbox providers. 

Let people unsubscribe from your emails with one click

Most of us have probably received some promotional emails that we're not particularly interested in. And when that happens, we want opting out to be simple. That's a big reason why Google and Yahoo have also updated their email subscription policies, aiming to improve the user experience and reduce unwanted email. 

Now, if you send more than 5,000 messages per day, you must implement a one-click unsubscribe process and honor any opt-out requests within 48 hours (previously, mailbox providers had up to 10 days to honor unsubscription requests). 

Attentive is working on accommodating this change behind the scenes, so if you're using our platform for email, meeting this new requirement is simple. 

Avoid sending unwanted emails to keep spam rates low

When you send emails to subscribers who are unengaged or uninterested, it can lead to complaints or a lack of engagement. As a result, more of your emails may be classified as unwanted and end up in the spam folder. Not only is this frustrating for recipients, but it also costs mailbox providers time and resources to process and store those unwanted emails.

To improve the email experience for everyone, Google and Yahoo have set guidelines that spam rates should be below 0.10% and never exceed 0.30%. This means that as a sender, it's important to be mindful of the content and recipients of your emails to avoid them being flagged as unwanted.

If you're an Attentive Email user, our Email Delivery Operations team will keep a close eye on your email traffic to ensure compliance with these guidelines (and work with you to improve your email program's deliverability, if necessary).

Email marketing deliverability best practices

Here are a few best practices to keep in mind as you continue to build your email marketing program. They offer insights into common issues, plus steps you can take to avoid them and improve your email deliverability. 

Minimize sign-up errors with double opt-in

One common cause of email delivery failure is when there's an error in the email address provided at sign-up. People can sometimes make mistakes when entering their email address, but using a double opt-in process for desktop sign-ups can help prevent typos from happening as much as possible. 

With a double opt-in, potential subscribers have to confirm their email address by clicking a verification link sent to their inbox. This step is essential for ensuring accuracy and staying compliant. Plus, it helps you avoid email bounces (i.e., invalid address, no such user), which can harm your sender reputation and hinder your ability to reach the primary inbox. 

‍Segment and personalize your emails 

Mailbox providers prioritize email placement based on recipient engagement, which means low engagement rates can lead to your emails being filtered into spam folders.

Segmenting your email list and tailoring your content to appeal to different groups of subscribers can help make sure that your messages keep landing in the inbox. Think about building dynamic audience segments based on your subscribers’ behavior, such as their browsing and purchase history and previous engagement, as well as their product or category preferences. 

The more relevant and interesting ‌your content is, the more likely someone is to click, and the better your email deliverability will be over time.

Avoid common spam triggers 

Spammy language and content formatting can also trigger spam filters. That includes things like excessive capitalization or punctuation, misleading subject lines, or having too many hyperlinks. 

Here are some general guidelines to keep in mind when crafting your emails: 

  • Write a clean subject line. Make it short and punchy, letting subscribers know what to expect so they'll want to open your email. Steer clear of words or phrases that could trigger spam filters (e.g., "free," "act now," "re:," "fwd:").
  • Keep the formatting simple. Your emails should be easy to read, with the most important information at the top. Use a mix of images and text to get your message across, and include a strong call to action that encourages readers to click.
  • Use hyperlinks sparingly. We recommend including no more than two or three links in your emails. Make sure all links are clearly clickable and have enough space around them so they're easy to click on mobile. 

Test and optimize your email strategy

To ensure your emails are engaging enough to land in the primary inbox, it's important to continuously test and refine them.

A/B testing different aspects of your email program can help you understand what works best for your audience (and what doesn't resonate with them as much). Then, you can use those insights to adapt your strategies accordingly. 

  • Subject line: Your subject line is the gateway to your email. It's the first thing your subscribers see, and it's crucial for grabbing their attention. Experiment with the tone, style, and language in your email subject lines to figure out what gets your subscribers to open them. 
  • Content: Once a subscriber opens your email, the content is what gets them to convert. Content includes your copy, images, call to action, and even the layout of your emails. Try testing these elements one at a time and comparing the performance to see which version performs better.
  • Send time: Generally speaking, there are some best times to send an email, but every audience is different. We recommend A/B testing when you send your campaigns to determine which times or days of the week your subscribers are most engaged.

Remember, an email with a great subject line and engaging content—sent at the right time—is more likely to be interacted with, which signals to email providers that your messages are relevant and, in turn, enhances your deliverability. 

Keep your email subscriber list clean 

Sometimes subscribers who were once active can go cold, and the last thing you want is to keep sending emails to people who aren't opening them. That lack of engagement could affect your sender reputation. 

Going through your email list regularly to remove inactive or unresponsive subscribers can help ensure that you’re only sending messages to people who want them. This is easy to do with sunset segments and journeys in Attentive Email, which allow you to identify and re-engage subscribers who haven’t opened or clicked on your emails in a while. 

You can even give these unengaged subscribers the option to opt out of your marketing emails altogether if they still aren’t responding after a few attempts to win them back. It may seem counterintuitive, but it's a smart move to increase your engagement rates.

How Attentive prioritizes email marketing deliverability

Monitoring for potential deliverability issues like low engagement rates, illegitimate addresses, bounces, and poor email formatting is really time-consuming. If you’re an Attentive customer, you’ll get deliverability support every step of the way (so you don’t have to do it yourself). 

We’ve intentionally built deliverability best practices into Attentive Email. With these tools and services—and a 99+% delivery rate—you can feel confident that your emails will make it to your customers' inboxes every time. We also have an expert team dedicated to managing relationships with internet service providers (ISPs), watching market trends, and monitoring your email activity to optimize performance. We measure open, click, spam complaint, bounce, and unsubscribe rates for each mailbox provider, so we can catch any issues early on and help preserve your sender reputation. 

Working with the right email service provider (ESP) is a critical first step in making sure your messages get where you want them to go. Learn more about Attentive Email and why it might be right for you today. 

Want to make sure your text messages make it to your subscribers, too? Here are our top tips for maximizing your SMS delivery.

Related Articles