In order to calculate the cost per call of all inbound calls coming into a call center, you must first determine the total operating costs for a given time period and the number of inbound calls. Then, divide the total costs by the number of inbound calls the call center received during the same time period. The resulting number will be the cost per inbound call. It is often useful to calculate call center costs using a short time period such as minutes, as opposed to per hour, since most calls are relatively short.
If the goal is cost reduction, there are two different methods for lowering the cost per call. One is to lower operating costs. These costs include things like the facility itself, telephones, electricity, and employee wages. The other way to reduce the cost per call is to increase the number of inbound calls coming into the call center.