Customer Acquisition Cost (CAC)

Customer Acquisition Cost measures the efficiency of a startup's go-to-market engine. It is calculated by dividing all sales and marketing spend in a period by the number of new customers acquired in that same period. A startup that spends ₹10 lakh on marketing and sales in a quarter and acquires 200 customers has a blended CAC of ₹5,000.

CAC is most meaningful when compared against two other numbers: Lifetime Value (LTV) and payback period. The LTV/CAC ratio tells investors whether the unit economics are sound — a ratio above 3:1 is a widely cited benchmark, meaning each customer generates at least three times what it cost to acquire them. Payback period converts this into time: if a customer contributes ₹2,000 in gross margin per month and CAC is ₹10,000, payback is 5 months. Shorter payback periods mean less working capital is tied up and the business can reinvest in growth faster.

Investors distinguish between blended CAC (all spend divided by all new customers, including organic) and paid CAC (spend on paid channels divided by customers from those channels). A low blended CAC driven by strong organic can mask an unsustainably high paid CAC — a vulnerability that surfaces when the company tries to scale. Founders should track both.

In Indian B2B markets, CAC is often elevated by long enterprise sales cycles, pre-sales support costs, and the need for local language collateral. These costs are frequently underestimated because founder time spent on sales is not always accounted for. Fully-loaded CAC must include salaries of everyone involved in the acquisition process.