Delivery rate is the percentage of sent emails that were successfully accepted by the recipient’s mail server. It is calculated by dividing the number of emails that did not bounce by the total number sent, then multiplying by 100.
A message is considered delivered once the receiving server accepts it, regardless of whether it ends up in the inbox or the spam folder. Delivery rate is therefore a measure of technical transmission success, not of inbox placement.
Delivery rate is one of the most fundamental metrics in email marketing because it sets the ceiling for everything else. If 10% of your emails are not being delivered at all, your open rates, click rates, and conversion data are all built on a reduced base. Persistent delivery failures, particularly hard bounces, also damage your sender reputation, creating a downward spiral where future sends become progressively less effective.
A healthy delivery rate is generally considered to be 95% or above. If yours is lower, the first step is to segment your bounce data: how many are hard bounces (permanent failures such as invalid addresses) versus soft bounces (temporary issues such as a full mailbox). Hard bounces should be suppressed immediately. For soft bounces, retrying once or twice before suppressing is common practice.
A delivery rate of 95% or higher is generally considered healthy across B2B email marketing. Top-performing programmes often achieve 98% or above. If your delivery rate drops below 90%, it is a strong signal that your list contains a significant number of invalid or abandoned addresses, or that your sending domain has a reputation issue that needs investigation.
Yes. Delivery rate measures whether the email was accepted by the receiving server, not where it was placed within the recipient’s mailbox. An email that is delivered directly to the spam folder is still counted as delivered in your delivery rate metric. Inbox placement rate, a separate, harder-to-measure metric, tracks how many emails land in the inbox versus spam.
The most effective steps are: removing hard bounces from your list immediately after they occur, using double opt-in to ensure addresses are valid at the point of collection, authenticating your sending domain with SPF, DKIM, and DMARC records, and regularly cleaning inactive or unengaged contacts from your list. Using a reputable email service provider with good infrastructure also gives you a head start on delivery.
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