Email Deliverability: Why Is It Important and How to Improve It?

Email deliverability is a crucial metric that gauges how your emails reach your intended recipients, making it a pivotal factor in the success of your email marketing campaigns.

Crafting content is futile if your emails are not being delivered. Email deliverability is a combination of various factors beyond audience building and sending emails. The first step in building a list of loyal customers is engaging with your audience through emails they want to read once, twice and more until things go south.

What Is Email Deliverability and How It Works

Email deliverability is a fundamental concept in email marketing and communication.  It refers to the process of ensuring your emails successfully reach the recipients’ inboxes without being flagged as spam or bouncing back. Essentially, it’s the measure of an email’s journey from the sender’s outbox to the recipient’s inbox.

Understanding Email Deliverability

Email deliverability entails more than the straightforward initiation of an email; it involves a multifaceted set of factors and processes that determine whether your email reaches its intended destination or ends up in a spam folder or gets rejected altogether. In essence, it’s about maximizing the chances that your email lands in the recipient’s inbox and gets noticed.

email deliverability
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Email deliverability involves a series of steps and checks that happen behind the scenes. Here’s a simplified overview of how it works:

  1. Sender Initiates Email: It all starts when the sender, which could be an individual or an organization, composes an email and hits “send.”
  2. Email Service Provider (ESP) Receives Email: The email is transmitted to the sender’s ESP (e.g., Gmail, Outlook, or a marketing automation platform).
  3. ESP Evaluates Email: The ESP performs various checks on the email, including sender authentication, content analysis, and recipient engagement history. It assesses the sender reputation and the email’s compliance with anti-spam regulations.
  4. Email Sent to Recipient’s Server: If the ESP approves the email, it is sent to the recipient’s email server.
  5. Recipient’s Server Evaluates Email: The recipient’s email server, which belongs to their ESP or organization, conducts further checks, including spam filtering, virus scanning, and recipient engagement analysis.
  6. Email Placed in Inbox or Spam Folder: Based on these evaluations, the email is either placed in the recipient’s inbox or routed to the spam folder. In some cases, emails may be rejected and not delivered at all.

Importance of Email Deliverability

Email marketing remains one of the most potent tools for businesses to engage with their customers, share valuable content, promote products or services, drive conversions, and most of the time that’s when you need to ensure the emails you send are delivered.

However, the power of email marketing can only be leveraged when your messages reach their intended recipients. This is where email deliverability plays a pivotal role.

Email Delivery vs. Email Deliverability

When it comes to understanding the effectiveness of your email campaigns, it’s essential to differentiate between email delivery and email deliverability. These two metrics provide distinct insights into the fate of your sent emails.

Email Delivery measures the number of emails that were successfully transmitted to their destination, regardless of where they land. It confirms that the recipient’s mail server accepted the email and didn’t bounce it back to the sender. In essence, it calculates the percentage of emails from your campaign that didn’t encounter delivery failures.

Email Deliverability, on the other hand, goes deeper into the journey of your emails. It focuses on the number of emails that not only reached their destination but also found their way into the recipient’s priority inbox. Email deliverability, also known as inbox placement, calculates the percentage of emails that achieved this coveted status.

email delivery vs email deliverability

How to Improve Email Deliverability

To ensure your emails consistently land in your recipients’ inboxes and are not flagged as spam, it’s essential to understand the factors that affect deliverability and implement best practices while avoiding common pitfalls.

Factors That Affect Deliverability of Emails

Several factors play a significant role in determining your email deliverability. Understanding these factors is the first step toward improving your email delivery rates:

  • Sender Reputation: Your sender reputation, built over time, is a crucial factor. A positive reputation enhances deliverability, while a negative one can lead to emails being marked as spam.
  • Email Content and Structure: The quality of your email content, subject lines, and HTML/CSS coding can impact whether your emails pass spam filters and reach the inbox.
  • Subscriber Engagement: Recipient engagement, measured by open rates and click-through rates, influences how email service providers (ESPs) view your emails. Engaged subscribers are more likely to receive your emails in their inbox.
  • Email Authentication: Implementing email authentication protocols like SPF, DKIM, and DMARC helps verify the authenticity of your emails and reduces the chances of them being marked as spam.

Best Practices to Improve Email Deliverability

Improving email deliverability is not a one-time fix but a continuous process. To enhance email deliverability and increase the chances of your emails reaching the inbox, consider implementing the following best practices:

1. Build a Positive Sender Reputation:

  • Maintain consistent sending practices.
  • Monitor and address recipient complaints promptly.

2. Optimize Email Content:

  • Craft engaging subject lines that encourage opens.
  • Avoid using spam trigger words or phrases in your content.

3. Enhance Subscriber Engagement:

  • Segment your email list for more targeted messaging.
  • Implement re-engagement campaigns for inactive subscribers.

4. Implement Email Authentication:

  • Set up SPF, DKIM, and DMARC to authenticate your emails.
  • Continuously monitor and manage authentication to ensure effectiveness

5. Maintain Proper IP Allocation:

  • As your email program grows, consider using a dedicated IP address once you reach 25,000 daily emails. Warming up a dedicated IP is essential to gain trust with ISPs. Avoid adding IPs indiscriminately, as this can lead to IP pool blocking.

6. Perfect the Opt-In Process:

  • Optimize your opt-in process to ensure your list comprises engaged users who willingly subscribed.
  • Double opt-in, which involves two verifications, is a successful method to build an engaged email list.

Email Deliverability Don’t-s

Awareness of what not to do is as important as knowing the best practices. It’s important to be aware of common pitfalls and avoid them:

  • Neglecting List Hygiene: Failing to regularly clean your subscriber list of inactive or invalid email addresses can negatively impact deliverability.
  • Ignoring Unsubscribe Requests: Make it easy for recipients to unsubscribe and respect their preferences. Ignoring unsubscribe requests can lead to spam complaints.
  • Overwhelming Recipients: Sending emails too frequently or at inappropriate times can lead to recipient fatigue and increased spam complaints.
  • Neglecting Email Content Quality: Poorly crafted emails with low-quality content are more likely to be marked as spam.
  • Neglecting Compliance: Failing to adhere to email marketing regulations and best practices can result in penalties and damage your sender reputation.

How to Test and Optimize for Email Deliverability

Achieving and maintaining high email deliverability rates is an ongoing endeavor that requires continuous monitoring, assessment, and refinement of your email marketing strategies. Detailed exploration of strategies for testing and optimizing email deliverability will empower you to fine-tune your email marketing efforts effectively and ensure that your emails consistently reach the intended inboxes of your recipients

Key Metrics for Email Deliverability

To effectively test and optimize email deliverability, it’s essential to first understand and monitor key metrics that serve as indicators of your email performance. These metrics offer valuable insights into the health of your email marketing campaigns and can guide your optimization efforts:

Key Metrics for Email Deliverability
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  • Delivery Rates: Delivery rates represent the percentage of emails that are successfully delivered to recipients’ inboxes. Monitoring delivery rates helps identify potential deliverability issues, such as emails being routed to spam folders or getting bounced.
  • Open Rates: Open rates indicate the proportion of recipients who open and view your emails. High open rates suggest that your emails are engaging and effectively reaching the inbox.
  • Click-Through Rates (CTR): CTR measures the percentage of recipients who click on links within your emails. It reflects the level of interest and engagement with your content, offering insights into the effectiveness of your messaging and design.
  • Bounce Rates: Bounce rates reveal the percentage of emails that couldn’t be delivered. They can be categorized into two types: hard bounces (due to invalid addresses) and soft bounces (temporary issues like a full inbox). Monitoring bounce rates is crucial for maintaining a clean email list.
  • Spam Complaint Rates: Spam complaint rates indicate the number of recipients who mark your emails as spam. A high spam complaint rate can have a detrimental impact on your sender reputation and email deliverability.
  • Unsubscribe Rates: Unsubscribe rates represent the percentage of recipients who opt out of your email list. While some unsubscribes are natural, consistently high unsubscribe rates should be addressed as they may signal issues with your content or email frequency.

Test Deliverability With This Tools

  • Email Authentication Checkers: Tools such as DMARC Analyzer and DKIM Validator help you ensure that your email authentication protocols (SPF, DKIM, DMARC) are correctly configured and authenticated, reducing the likelihood of your emails being marked as spam.
  • Inbox Placement Testers: Services like GlockApps and Return Path provide sophisticated inbox placement testing, allowing you to see precisely where your emails land in various email clients and internet service providers (ISPs), and providing guidance on how to improve your inbox placement rates.
  • Spam Filter Testing Tools: Tools like Litmus and SpamAssassin assess your emails for potential spam triggers and provide detailed feedback to help you avoid spam filters and improve deliverability.
  • Sender Reputation Monitors: Services like Senderscore and Barracuda Reputation Blocklist (BRBL) allow you to track and improve your sender reputation, which is a crucial factor in email deliverability.
  • Email List Cleaners: Tools such as NeverBounce and ZeroBounce assist in cleaning your email list by identifying and removing invalid, duplicate, or risky email addresses, ensuring that you send emails only to engaged and valid recipients.
  • Email Deliverability Analytics Platforms: Platforms like 250ok and Validity offer robust email deliverability analytics and reporting. They provide in-depth insights into your email performance, including detailed metrics, recommendations, and guidance on how to optimize your campaigns for better deliverability.

Email deliverability is a vital aspect of email marketing that directly impacts campaign success, customer engagement, and brand reputation. By understanding its importance, differentiating between delivery and deliverability, addressing key factors, and utilizing best practices and tools, you can enhance your email deliverability and maximize the impact of your email marketing endeavors.