Abandonment rate is the percentage of contacts that entered a queue but gave up — hung up, closed the chat — before being served. It is a direct read on whether wait times have crossed the customer's patience threshold, and it pairs naturally with service level.
The formula is abandoned contacts over total contacts offered.
What it hides: not every abandon is a failure. Very short abandons (misdials, someone who found the answer while waiting) inflate the number, which is why serious teams exclude abandons in the first few seconds. And a low abandonment rate bought with a callback deflection or a discouraging IVR isn't really a win.