Customer acquisition cost (CAC) is the amount of money a company spends to get a new customer. It helps measure the return on investment of efforts to grow their clientele. CAC is calculated by adding the costs associated with converting prospects into customers (marketing, advertising, sales personnel, and more) and dividing that amount by the number of customers acquired.

To calculate CAC, follow these steps for a given time period (month, quarter, or year):

Add up program or advertising spend + salaries + commissions + bonuses + overhead.
Divide by the number of new customers in that time period.
For example, if you spend 500.000 € on Sales and Marketing in a given month and added 50 customers that same month, then your CAC was 10.000 € that month.