What Is Customer Acquisition Cost (CAC)?
Customer Acquisition Cost (CAC) is the total sales and marketing cost required to acquire a single new customer, calculated by dividing total acquisition spend by the number of customers gained.
CAC, Explained Simply
How much does it actually cost to win one new customer?
CAC adds up everything spent on sales and marketing over a given period — advertising, tools, salaries, and programs — and divides that by the number of new customers acquired in that period.
The resulting number represents the average cost to bring on one new customer.
CAC is most meaningful when viewed alongside how much revenue that customer is expected to generate over time.
Why CAC Matters
CAC is a foundational efficiency metric for any growing business. It helps teams:
- Understand the true cost of growth
- Evaluate whether acquisition spend is sustainable
- Compare acquisition efficiency across channels or segments
- Set realistic budgets for sales and marketing
- Inform pricing and customer lifetime value decisions
A rising CAC without a corresponding rise in customer value is an early warning sign worth investigating.
PAULA'S PERSPECTIVE
CAC is one of those numbers that looks simple on the surface but tells you a lot about the health of a go-to-market strategy once you dig in.
I always want to know how CAC is trending over time, not just what it is in a single quarter. A slowly rising CAC might be fine if lifetime value is rising faster. A rising CAC on its own is a red flag.
It's also worth breaking CAC down by channel and segment rather than looking only at a blended average. That's where you find out which parts of the business are actually efficient.
CAC should never be evaluated on its own. It only means something in relation to what that customer is ultimately worth.
— Paula Chiocchi
CAC in Practice
- Step 1Total Acquisition Spend
- Step 2New Customers Counted
- Step 3CAC Calculated
- Step 4Segments Compared
- Step 5Strategy Adjusted
A B2B company totals its quarterly sales and marketing spend and divides it by the number of new customers acquired in that period.
By breaking CAC down by channel, the team discovers that outbound sales efforts cost significantly more per customer than inbound marketing, informing where to focus future investment.
KEY TAKEAWAY
CAC measures the average cost to acquire a new customer, helping businesses evaluate growth efficiency and sustainability alongside customer lifetime value.
About Paula Chiocchi
Paula Chiocchi is the Founder and CEO of Outward Media, Inc. and host of B2B Influence: Spotlight on Industry Game-Changers, with decades of experience in data-driven marketing.