16th November 2022 by 
Open rates, click rates and the number of people who unsubscribe, are all important email statistics to track when sending out email marketing campaigns. But another statistic, email deliverability is often neglected.
Email deliverability is an important statistic to gleam meaningful results from your emails. Here, we provide an introduction to email deliverability and explain how emails are tested by the mail servers before they reach their intended inbox.
Email deliverability, what is it?
The likelihood of an email been delivered into an inbox is how email deliverability is defined.
We tend to assume that when sending emails to multiple recipients, the email will successfully reach their inboxes. This isn’t always the case.
After taking the time crafting the perfect email, pruning the recipient mailing list and hitting send, you find only 70% of the mailing list received your email. It can be frustrating to many a digital marketing expert, digital designer or email developer.
So why wasn’t the email delivered to the remaining 30%? When your email reaches a mail server, it is analysed for any potential issues or errors.
However, the answer is not always clear cut when it comes to deliverability.
The common reasons are:
- Email providers are marking your email has spam
- The email address is invalid
- It went into the junk folder
- The email is blocked by the mail server
- Your email server is blacklisted.
Email authentication
Authenticating emails has the purpose of safeguarding recipients from potentially spammy and malicious emails. This authentication process determines the email deliverability. The important areas of this authentication process are SPF, DKIM and DMARC.
Sender Policy Framework (SPF)
This framework prevents spammers using your own domains to send out emails. A SPF record is added to the Domain Name System (DNS) of your domain. This allows you to specify which IP addresses and hostnames are allowed to send emails out using your domain. Through the implementation of a SPF record, any unauthorised emails are marked as suspicious and rejected. Basically, preventing the emails from landing within inboxes.
DomainKeys Identified Mail (DKIM)
DKIM is a security standard to ensure that emails do not change between the time they were sent and when it lands in the inbox. DKIM is used to validate that the email came from a trustworthy mail server.
Essentially, a private key signs the email at the time of the send. A public key attached to the sender domain is used by the receiving mail server to verify that the email has not been forged. Furthermore, the DKIM confirms that the content has not changed during it’s way into the inbox.
Using DKIM signatures is safer and more legitimate. Therefore, your email deliverability will improve as a result.
Domain-based Message Authentication Reporting and Conformance (DMARC)
Another email authentication protocol is DMARC. This is designed to prevent people using a domain they do not own themselves and using the domain without the knowledge of the legitimate owner. Moreover, this protocol protects businesses against cybersecurity threats, scams and phishing emails that are ever becoming more commonplace.
The domain owner creates instructions within the DNS settings. These instructions are used by the mail server to authenticate all emails that attempt to reach a specific inbox. Furthermore, this protocol is an extension to both SPF and DKIM. So, in combining the benefits of both helps the server to perform a in-depth analysis of the incoming email.
Summary
The above is quite a bit to take in, so here is a summary:
- SPF authentication enables email senders to specify which IP addresses are permitted to send emails from a certain domain
- DKIM employs a signature and encryption key to make sure emails haven’t been tampered with in any way on route
- Both types of authentication are used by DMARC to guard against online threats and unauthorised use of its domain.
We have been running email campaigns for years and have continually learned from experience of how to enhance not just email deliverability, but open rates and click rates. If you want help to improve your email campaign results, why not consider us to help you out. We have the expertise and we would love to help you.
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