What is Customer Acquisition Cost (CAC)?
Customer Acquisition Cost (CAC) is the total sales and marketing spend required to win a new customer, divided by the number of customers acquired in that period. It answers a fundamental question: how much does growth cost?
CAC is judged in context, primarily against Customer Lifetime Value (LTV). If it costs more to acquire a customer than they're ever worth, growth destroys value. Teams also track CAC payback period — how many months of revenue it takes to recoup acquisition cost — as a measure of capital efficiency.
While CAC is often owned by marketing, PMs influence it heavily. Product-led growth, referral loops, and strong activation can lower effective CAC by turning users into a distribution channel, reducing reliance on paid acquisition.
Examples
- Spending $100k on marketing to acquire 1,000 customers yields a CAC of $100.
- A PM builds an in-product referral loop that lowers blended CAC by driving organic signups.
Where PMs use this
Related terms
Customer Lifetime Value (LTV)
The total revenue (or profit) a business expects to earn from a customer over the entire relationship.
Conversion Rate
The percentage of users who complete a desired action out of those who had the opportunity.
Unit Economics
The direct revenues and costs associated with a single unit (usually a customer), revealing whether a model is profitable.
Go-to-Market (GTM)
The plan for how a product reaches its target customers — positioning, pricing, channels, and launch.