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The Difference Between Deliverability and Email Delivery Rate

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    If you’re responsible for maintaining the performance of your organization’s email marketing program, it’s essential to know the difference between deliverability and email delivery rate. 

    Many people confuse them as one in the same; however, they have different meanings and effects on an advertising program. 

    Deliverability is a measure of how successfully emails are sent through networking or ISP servers to reach an inbox while delivery rate is an indicator showing how many emails actually reach the recipient’s inboxes after being sent. 

    In this blog post, we’ll explore both terms in detail and explain why understanding their difference can help you optimize your email campaigns!

    What is email delivery rate?

    Email delivery rate refers to the percentage of emails that are successfully delivered to recipients’ inboxes, out of the total number of emails sent. It is a key performance indicator (KPI) used in email marketing to measure the effectiveness of an email campaign and the ability of an email service provider (ESP) to deliver emails to the intended recipients.

    Email delivery rate is calculated by dividing the number of emails delivered to recipients’ inboxes by the total number of emails sent, and then multiplying by 100 to express it as a percentage. It is typically monitored and analyzed along with other email marketing metrics such as open rate, click-through rate (CTR), and conversion rate to assess the overall performance of an email campaign.

    A high email delivery rate indicates that a significant portion of emails are reaching the intended recipients, which is important for successful email marketing campaigns. 

    Factors that can impact email delivery rate include sender reputation, email content, recipient engagement, and email service provider settings. 

    Monitoring and optimizing email delivery rate can help improve the effectiveness of email campaigns and ensure that messages are reaching the desired audience.

    Difference between deliverability and email delivery rate

    Many people use the terms deliverability and delivery rate interchangeably. However, there is a difference between the two that should be understood for a successful email marketing campaign.

    Email deliverability refers to the number of emails that make it to the recipient’s inbox or are delivered to a mail server without being marked as spam or rejected. It is affected by a range of factors such as email authentication, reputation, content and formatting, bounces, etc. All of these elements influence an email’s chances of reaching the intended recipient.

    Deliverability refers to the ability of an email to successfully reach the recipient’s inbox, without being filtered as spam or blocked by email service providers (ESPs) or internet service providers (ISPs). It is a measure of the overall success of an email reaching its intended destination without being flagged as unwanted or malicious.

    Email delivery rate, on the other hand, is the percentage of sent emails that have been delivered to the recipient, whether to their inbox or their spam folder. It is calculated by dividing the number of successfully delivered emails by the total number of sent emails.

    While email deliverability is certainly important, the email delivery rate ultimately determines how many recipients actually received and potentially opened the email. 

    In other words, deliverability is a broader concept that encompasses the overall success of emails reaching recipients’ inboxes, while email delivery rate is a specific metric that quantifies the proportion of emails that are successfully delivered out of the total emails sent.

    If an email is successfully delivered but ends up in the recipient’s spam folder, it is still considered to be delivered. In this sense, email delivery rate has a direct impact on the effectiveness of the marketing campaign.

    Email delivery rate formula

    Email Delivery Rate (%) = (Number of Emails Delivered to Inbox / Total Number of Emails Sent) x 100

    To use this formula, you need to know the number of emails that were successfully delivered to recipients’ inboxes and the total number of emails sent in a specific email campaign or time period.

    For example, if you sent 10,000 emails and out of those, 9,000 were delivered to recipients’ inboxes, the email delivery rate would be:

    Email Delivery Rate = (9,000 / 10,000) x 100 = 90%

    This means that 90% of the emails sent were successfully delivered to recipients’ inboxes, while 10% may have bounced, been filtered as spam, or otherwise not reached the intended recipients. Monitoring and analyzing email delivery rate can provide insights into the success of your email campaigns and help you optimize your email marketing strategies for better results.

    Factors that affect the email delivery rate

    ✅ The reputation of the sender's domain and IP address

     ISPs and ESPs evaluate the sender’s reputation to determine whether an email should be delivered to the inbox or flagged as spam. Factors that can affect sender reputation include sending history, email engagement metrics (such as open rates and click-through rates), spam complaints, and overall sender practices, such as list quality and authentication.

    ✅ The content of the email

    Including the subject line, body, and attachments, can impact deliverability. Emails with suspicious or spammy content, excessive use of capital letters, excessive use of exclamation marks, or too many hyperlinks may trigger spam filters and result in lower email delivery rates.

    ✅ The quality of the email list

    Using outdated or purchased email lists, or sending emails to inactive or unengaged recipients can result in higher bounce rates and lower email delivery rates. It’s important to maintain a clean and engaged email list to improve email deliverability.

    ✅ Authentication

    Proper email authentication, such as DKIM (DomainKeys Identified Mail) and SPF (Sender Policy Framework), helps verify the authenticity of the sender and can improve email deliverability. These authentication methods provide additional credibility to the sender, reducing the chances of emails being flagged as spam.

    ✅ The engagement of recipients with previous emails

    Such as open rates, click-through rates, and overall interaction, can impact deliverability. ISPs and ESPs may consider recipient engagement as a factor in determining whether an email should be delivered to the inbox or marked as spam.

    ✅ ESP Settings

    The configuration and settings of the email service provider (ESP) used to send emails, including sending frequency, sending limits, and other technical settings, can also impact email delivery rates. It’s important to ensure that the ESP is properly configured and aligned with industry best practices.

    ✅ ISP Filtering

    ISPs and ESPs have their own filtering algorithms that can filter emails as spam or send them to the inbox. These algorithms consider a variety of factors, including sender reputation, content, and engagement, to determine email deliverability.

    ✅ Technical issues

    Such as email server misconfiguration, DNS issues, or email authentication failures, can impact email delivery rates. Regular monitoring and maintenance of technical settings can help prevent such issues from affecting deliverability.

    How to improve email deliverability?

    There are several ways to improve email deliverability and increase the chances of your emails being successfully delivered to your recipients’ inboxes. One of the most important factors to consider is the quality of your email content. To improve email deliverability, it is crucial to write with more details and facts, as well as higher semantic richness.

    The first step is to ensure that your email content is relevant and valuable to your subscribers. This means that the content should be tailored to the specific interests and needs of your audience. You should also use a clear and concise writing style that is easy for your subscribers to understand.

    Another important factor to consider is the use of keywords and phrases. By including relevant keywords and phrases in your email content, you can improve the relevance and authenticity of your emails. This can help to increase the likelihood that your emails will be delivered to your subscribers’ inboxes.

    In addition, it is important to pay attention to the length and formatting of your email content. Keep your messages short and to the point, while also ensuring that they are visually appealing and easy to read. The use of headings, subheadings, and bullet points can help to break up your content and make it more user-friendly.

    Finally, it is important to ensure that your email content is properly optimized for mobile devices. With an increasing number of people accessing their emails on mobile devices, it is imperative to ensure that your emails are mobile-friendly. This means using a responsive design and ensuring that your emails are easily readable on all types of devices.

    By improving the quality of your email content, you can increase the likelihood that your emails will be successfully delivered to your subscribers’ inboxes. By following these simple tips, you can improve your email deliverability and ensure that your messages are read by your target audience.

    Make it to the inbox, not the spam folder, with Warmy.io

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    Although there is an often-overshadowed difference between deliverability and email delivery rate, understanding them can be a crucial boon to your email marketing efforts. 

    Delivering emails is an extremely important part of running an effective and successful email campaign, as the only way to make sure that emails reach the intended recipients. Meanwhile, deliverability directly impacts how much traffic your emails can generate for your organization. 

    Poorly managed campaigns do not allow marketers to control their own destiny when it comes to using email as a communication tool. It takes careful consideration, strategy, and analysis to ensure success in achieving long-term deliverability rates. 

    Taking the time to refine processes and troubleshoot any issues encountered with delivering your messages will be one of the most beneficial investments you’ll ever make for your organization.

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