Customer Acquisition Cost (CAC)
CAC is how much money you spend to get one new customer. If you spend $10,000 on marketing and sales in a month and get 100 new customers, your CAC is $100. Lower is generally better, but only if you're still reaching the right customers.
Customer Acquisition Cost (CAC) is the total cost of acquiring one new customer, including all sales and marketing expenses. Alongside LTV, it is a core unit economics metric that determines whether a business is viable at scale.
CAC formula:Total sales and marketing spend ÷ New customers acquired in the period
For a company spending $500,000/quarter on sales and marketing and acquiring 200 new customers: CAC = $500,000 / 200 = $2,500
Blended vs. paid CAC:Blended CAC includes all acquisition channels. Paid CAC isolates only paid channels. Organic CAC (from SEO, referrals, word-of-mouth) is often significantly lower — companies with strong organic engines have structural CAC advantages.
CAC by channel:Breaking CAC down by acquisition channel reveals which channels are most efficient and where to concentrate investment.
CAC payback period:How long it takes to recover CAC from gross profit. Most SaaS investors look for payback periods under 12–18 months.
CAC trends:Rising CAC over time is a significant concern — it often indicates market saturation, increased competition, or diminishing returns from existing channels.
Key Takeaways
- CAC should always be compared to LTV — a low CAC is only good if LTV also exceeds it significantly
- Blended CAC masks channel efficiency — measure CAC by channel for investment decisions
- Organic CAC from SEO, word-of-mouth, and referrals is a structural competitive advantage
- Rising CAC trend is often an early warning of go-to-market or market saturation problems
Common Questions
What's included in CAC calculation?
Include: all marketing spend (ads, content, events, tools), all sales spend (SDR/AE salaries, commissions, tools), and sales/marketing overhead. Some calculations also include onboarding costs if they're significant relative to deal value.
Is it normal for CAC to increase over time?
Some CAC increase is normal as you move up-market or enter new segments. Significant CAC inflation beyond market growth typically indicates exhaustion of efficient early channels — a signal to diversify acquisition.