Email Deliverability Full Guide + Free Ebook

Email deliverability is a big deal for anyone serious about email marketing. Simply put, email deliverability is about making sure your emails actually reach the inboxes of your subscribers, rather than getting lost in spam folders, sent to the often-ignored promotion folder,  or bouncing back undelivered.

This guide will take you through everything you need to know to improve your email deliverability, including practical tips and tricks that you can start using right away. If you’re just getting started or even looking to up your game, this guide has you covered.

What is email deliverability?

Email deliverability is making sure your emails land where they’re supposed to – in your subscribers’ inboxes. It’s the measure of how successful an email campaign is at reaching your intended audience without getting flagged as spam or bouncing back.

When your emails don’t make it to the inbox, you’re not just losing out on potential opens and clicks; you’re also risking your sender reputation, which can make it even harder to reach your audience in the future.

What is considered good email deliverability?

Good email deliverability is typically measured by the percentage of emails that successfully reach your recipients’ inboxes.

Firstly, to calculate your email deliverability score, you just need to use a simple formula.

Email Deliverability Rate Formula
Email Deliverability Rate = (Number of Emails Delivered / Number of Emails Sent) x 100
  • Emails Sent refers to the total number of emails that were attempted to be sent to recipients.
  • Emails Delivered refers to the emails that successfully reached the recipient’s email server and did not bounce.

Once you have your percentage score, you’ll know how good your deliverability is.

For example, if you sent 1,000 emails and 950 were delivered, the calculation would be:

Email Deliverability Rate = (950 / 1000) x 100 = 95%

Here’s a quick breakdown of what your score means:

  • 80-85% deliverability rate: This is considered average. It indicates there’s room for improvement, as some emails may be getting filtered out or bouncing back.
  • 85-95% deliverability rate: This is considered a solid deliverability rate. Most of your emails are reaching inboxes, but there’s still some room for refinement.
  • 95%+ deliverability rate: This is excellent. You’re doing a great job at making sure your emails are landing where they should be!

How to test email deliverability

Testing your email deliverability is crucial to understanding how well your emails are performing and identifying any potential issues that could be holding you back. Here’s a list of tools that can help you assess and improve your email deliverability:

  1. Warmup Inbox: This tool is designed to help you gradually improve your sender reputation by automating the process of sending warmup emails. By slowly increasing your email volume and interactions, Warmup Inbox helps your emails be seen as trustworthy by ISPs, thereby improving your overall deliverability.
  2. EmailListVerify: EmailListVerify is for cleaning up your email list. Through verifying and validating your email addresses, it ensures that your emails are only sent to valid addresses, reducing bounce rates and improving deliverability. It checks for syntax errors, invalid domains, and disposable emails, helping you maintain a high-quality email list.
  3. MxToolbox: MxToolbox offers a suite of tools to help you diagnose and fix deliverability issues. It includes blacklist checks, DNS diagnostics, and more, helping you ensure your emails are properly configured for optimal delivery.
  4. GlockApps: GlockApps allows you to test where your emails land—whether they end up in the inbox, spam folder, or get blocked entirely. It provides detailed reports on your email campaigns and suggests improvements to boost your deliverability.

What affects email deliverability?

Several factors can impact whether your emails make it to the inbox or get stuck in the spam folder. Understanding these elements can help you optimize your email campaigns for better deliverability:

  1. Sender reputation: This is the backbone of your email deliverability. ISPs look at your sending history, including how often your emails are marked as spam, your bounce rate, and your engagement metrics. A poor sender reputation can drastically reduce your deliverability.
  2. Email content: The content of your emails plays a part in deliverability. Spammy language, excessive use of images, or even certain keywords can trigger spam filters. Writing clear, concise, and relevant content helps avoid these pitfalls.
  3. Email authentication: Authentication protocols like SPF, DKIM, and DMARC are essential. They verify that your emails are coming from a legitimate source and aren’t being spoofed by spammers.
  4. Email list quality: A clean, updated email list is vital for high deliverability. Invalid or outdated email addresses increase your bounce rate, which negatively impacts your sender reputation.
  5. Engagement rates: ESPs monitor how recipients interact with your emails. High open rates, click-through rates, and low bounce rates signal that your emails are welcomed by recipients, improving deliverability.
  6. Frequency and volume: Sending too many emails in a short period can be a red flag for ESPs, especially if you suddenly increase your volume. Consistency in your sending frequency is key to maintaining a good reputation.

Types of email bounces

When you send an email and it doesn’t reach the recipient, it’s often because of an email bounce. Bounces can be classified into two main types: hard bounces and soft bounces.

Hard email bounces

A hard bounce happens when an email cannot be delivered due to a permanent issue. This could be because the recipient’s email address is invalid, the domain name no longer exists, or the email server has blocked your email. Here’s how you can address and avoid hard bounces:

Causes:

  • Invalid email addresses (typos, defunct domains, etc.)
  • Blocked email addresses or domains
  • Non-existent email servers

How to fix it:

  • Use email verification tools: Regularly clean your email list using tools like EmailListVerify to remove invalid addresses and prevent hard bounces from affecting your sender reputation.
  • Validate emails during signup: Implement real-time email validation on your sign-up forms to catch typos and invalid addresses before they make it onto your list.

Soft email bounces

A soft bounce happens when an email fails to be delivered due to a temporary issue. This might be because the recipient’s inbox is full, the server is down, or the message is too large. While soft bounces are less severe than hard bounces, they still need to be monitored and managed.

Causes:

  • Recipient’s inbox is full
  • Temporary server issues
  • Email size exceeds server limits

How to fix it:

  • Monitor and retry: Many email service providers will automatically retry sending a soft-bounced email. Keep an eye on your bounce reports and ensure that these emails are successfully delivered in subsequent attempts.
  • Check email size: Make sure your emails are optimized in size by compressing images and avoiding large attachments to prevent soft bounces related to message size.

How to improve email deliverability

Boosting your email deliverability is all about adopting best practices that keep your emails from being flagged as spam and ensure they reach your recipients’ inboxes. Below are 10-15 actionable tips to help you improve your email deliverability.

1. Authenticate your emails with SPF, DKIM, and DMARC

Email authentication protocols like SPF, DKIM, and DMARC verify that your emails are legitimate and help prevent spoofing. Setting these up tells ISPs that your emails are trustworthy.

Source: Mimecast

Tip:
Use tools like the free DNS health checker to check if your domain has these protocols properly configured.

2. Clean your email list regularly

A clean email list is a happy email list. Regularly removing invalid addresses reduces hard bounces and improves your sender reputation.

Tip:
EmailListVerify can help you clean up your email list by detecting and removing invalid or disposable email addresses.

3. Segment your audience

Segmenting your email list allows you to send more relevant content to your subscribers, which can increase engagement and reduce the likelihood of your emails being marked as spam.

Tip:
You might create segments based on purchase history, engagement level, or geographic location to tailor your content more effectively.

4. Monitor your sender reputation

Email sender reputation factors

Your sender reputation plays a huge role in email deliverability. Regularly monitor your sender score to make sure your reputation stays in good standing.

Tip:
Warmup Inbox provides insights into your sender reputation and helps you identify areas for improvement through an easy-to-read report right in your inbox.

5. Avoid spammy language

Words like “free,” “guaranteed,” and excessive use of exclamation marks can trigger spam filters. Keep your language professional and clear.

Tip:
Use our free spam words checker to scan your emails for any spammy content before sending.

6. Keep your emails concise

Nobody likes a long-winded email. Get to the point quickly, and make sure your emails are easy to read and relevant to the recipient. The best emails are between 50 – 125 words long.

Tip:
Stick to a clear structure with a strong headline, brief content, and a compelling call to action (CTA).

7. Encourage engagement

Encourage your subscribers to engage with your emails by including CTAs that prompt them to click, reply, or forward. High engagement rates signal to ISPs that your emails are valuable, and clear, concise CTAs can increase engagement by 161%!

Tip:
Try using Deadline Funnel to create a sense of urgency with a countdown timer in your emails.

8. Test your emails before sending

Always run tests on your emails to check how they’ll appear in different email clients and ensure they don’t trigger spam filters.

Tip:
Use tools like Litmus or Email on Acid to preview how your emails will look in various email clients and devices.

9. Keep an eye on your bounce rates

High bounce rates can hurt your sender reputation. Monitor your bounce rates closely and take action to reduce them.

Source: The Online Advertising Guide

Tip:
Review your email analytics after each campaign to identify and remove any problematic addresses.

10. Use a reputable email service provider (ESP)

Choosing a reliable ESP is key to ensuring your emails are delivered successfully. Look for providers with good deliverability rates and robust features.

Tip:
Take a look at our list of the best email service providers to get all the info on the most reputable services.

11. Warm up new IP addresses

If you’re using a new IP address to send emails, start by sending small volumes of emails and gradually increase over time. This helps build your reputation with ISPs.

Tip:
Warmup Inbox can help automate the process of warming up new IP addresses

12. Set expectations with a welcome email

When someone subscribes to your list, send a welcome email that sets expectations about what they’ll receive and how often. This helps prevent future unsubscribes and spam complaints.

Tip:
Include a clear explanation of the content they’ll receive and an option to update their preferences.

13. Offer easy opt-outs

Make it simple for recipients to unsubscribe if they’re no longer interested. An easy opt-out process reduces the chance of your emails being marked as spam. In many places, it’s also part of the law to include a visible, easy opt-out.

“Your message must include a clear and conspicuous explanation of how the recipient can opt out of getting marketing email from you in the future. Craft the notice in a way that’s easy for an ordinary person to recognize, read, and understand.

Creative use of type size, color, and location can improve clarity. Give a return email address or another easy Internet-based way to allow people to communicate their choice to you.” – Federal Trade Commission

Tip:
Ensure the unsubscribe link is clearly visible and easy to use in every email you send, and try using some creative flair.

14. Monitor inbox placement

Just because an email is delivered doesn’t mean it’s landing in the inbox. Use tools to check whether your emails are being delivered to the inbox, spam, or promotions tab.

Tip:
Use our free inbox placement tester to test your emails in a safe environment before sending them out to your list.

15. Keep your sending frequency consistent

Sudden changes in your sending frequency can raise red flags with ISPs. Maintain a consistent sending schedule to avoid deliverability issues.

Tip:
If you send emails weekly, try to stick to that schedule as closely as possible, rather than sending sporadically.

Conclusion

Improving email deliverability isn’t a one-time task; it’s an ongoing process that requires consistent monitoring and adjustments.

Utilize the tools and tips mentioned in this guide to keep your emails out of the spam folder and in front of the right eyes.

For a more in-depth exploration, don’t forget to download our comprehensive ebook on email deliverability, packed with actionable insights and strategies to take your email campaigns to the next level.

Laura Clayton

Laura is an email marketing expert specializing in email warmup strategies to enhance deliverability. She shares concise, actionable insights to help businesses improve their email outreach and connect effectively with their audience.