When running email campaigns or sending individual emails, accurately tracking whether emails are successfully delivered is critically important. However, the reliability of delivery reports can vary depending on several factors. In this article, you’ll find detailed explanations of email delivery statuses and the reliability of tracking processes.
Accuracy of Email Delivery Reports
In email marketing, delivery and deliverability tracking are generally 90–99% accurate, but there are important considerations:
🔹 Successfully Delivered Emails:
Most Email Service Providers (ESPs) report “delivered” statuses with up to 99% accuracy, based on server response reports.
🔹 Error/Bounce Rates (Bounced Emails):
Invalid addresses (hard bounces) or temporary issues (soft bounces) are usually correctly detected and reported.
🔹 Emails Caught by Spam Filters:
An email may be technically “delivered” but end up in the spam folder, which ESPs usually cannot detect.
🔹 Open and Click Tracking:
Done through tracking pixels and tracked links, but privacy protections (like Apple Mail Privacy Protection) can affect accuracy.
Summary:
✅ Delivery status is usually tracked with 90–99% accuracy.
⚠ Spam filtering and privacy settings may lower tracking precision.
🔍 For better analysis, focus not only on opens and clicks but also on conversions (sales, form submissions, etc.).
Common Email Delivery Statuses and Their Meanings
Here are the most frequently encountered email statuses, explained:
1. Sent
The email was successfully sent to the recipient’s mail server but may not have reached the inbox yet.
2. Delivered
The email was accepted by the recipient’s server and likely reached their inbox.
3. Not Reached
The email failed to reach the recipient due to various reasons, such as invalid addresses or full mailboxes.
4. Hard Bounce
The email could not be delivered permanently. This usually happens due to invalid, closed, or incorrect email addresses.
Important:
Incorrect or missing DNS settings (SPF, DKIM, DMARC) on the sender’s domain can also increase hard bounce rates. Proper DNS configuration is crucial for healthy deliveries.
5. Blocked
The email was actively rejected by the recipient’s server, possibly due to blacklisting or spam filters.
6. Marked as Spam
The email was flagged as spam by the recipient or their mail server, harming the sender’s reputation.
7. Unknown
The delivery status could not be determined, usually due to network issues or incomplete reporting between servers.
8. Opened
The recipient opened the email, detected via a tracking pixel. However, privacy protections may affect this data’s accuracy.
9. Clicked
The recipient clicked a link inside the email, a critical metric for measuring engagement.
10. Invalid
The email address was incorrectly formatted (e.g., missing @ sign or domain).
11. Queued
The email is queued for sending but hasn’t been sent yet, possibly due to server load or scheduled delivery.
12. Unsubscribed
The recipient unsubscribed manually or was automatically removed after multiple bounces or spam complaints.
13. Invalid/Blocked/Spam Flagged Address
This status indicates addresses that are invalid, blocked, or previously marked as spam. Further sending is not recommended.
14. Error
A technical problem occurred during the sending process, such as server issues or configuration errors. The email was not sent at all.
Tips to Improve Email Deliverability
Follow these best practices to ensure successful email delivery:
✅ Keep Your Email Lists Clean
Regularly remove invalid or non-responsive addresses.
Identify inactive subscribers.
✅ Properly Configure DNS Settings
Ensure your SPF, DKIM, and DMARC records are correctly set.
Regularly check if your IP address or domain is blacklisted.
✅ Reduce Spam Risks
Avoid spam-triggering words like “free,” “win now,” excessive exclamation marks, or full caps.
Maintain a good text-to-image ratio.
✅ Manage Frequency and Permissions
Use opt-in systems to get permission from recipients.
Avoid overwhelming users with too many emails.