1. Customer Service

10 Email-Based Customer Support KPIs

Agent Email Handling Time

The average time an agent spends on an email, from reading it to sending a response.

Email Backlog #

The number of unresolved or unopened emails at any given time.

Email Case Reopen Rate %

The percentage of email cases that were marked as resolved but had to be reopened due to the issue not being adequately addressed.

Emails Per Resolution #

The average number of email interactions required to resolve a customer's issue.

Email Template Usage Rate %

The percentage of emails sent using predefined templates versus manually written emails.

Email Volume #

Email Volume measures the number of emails or inquiries your team receives via email during a specific time period.

Internal Response Time

The average time taken for one support agent to respond to another agent's internal query or request related to an email case, in minutes.

Missed Emails #

The number of customer emails that were overlooked or not responded to.

Proactive Emails Sent #

The number of emails sent to customers proactively, not as a direct response to a customer's email.


The average time it takes from the initial customer email to the resolution of their query or issue (hours or days).