What is Customer Acquisition Cost (CAC)?
Customer Acquisition Cost is the total cost of winning a new customer, including all marketing spend, sales team costs, tools, and overhead. It is the foundational unit economic metric, if your CAC exceeds what a customer is worth (LTV), your business model is unsustainable. Every dollar of CAC must eventually be recovered through customer revenue.
The Formula
CAC = (Total Marketing Spend + Total Sales Spend) ÷ Number of New Customers Acquired
Include salaries, commissions, software tools, agency fees, content creation costs, and ad spend for a fully-loaded CAC.
Worked Example
A B2B SaaS company spends $40,000 on marketing and $25,000 on sales (including salaries) in a month, acquiring 50 new customers.
- Total Acquisition Spend = $40,000 + $25,000 = $65,000
- New Customers = 50
- CAC = $65,000 ÷ 50 = $1,300 per customer
- If average LTV is $5,200, then LTV:CAC = 4:1 ✓
📌 At $1,300 CAC with a $5,200 LTV, the company has a healthy 4:1 ratio, well above the 3:1 minimum most investors look for.
Why This Matters
Unit economics validation
If CAC exceeds LTV, you lose money on every customer you acquire. Use the Unit Economics Calculator to check your ratio.
Channel optimization
Calculating CAC by channel reveals which channels deliver customers most efficiently. Compare against your ROAS and cost per lead to reallocate budget.
Investor due diligence
VCs examine CAC trends closely. A rising CAC signals market saturation. Track it alongside your SaaS metrics dashboard for the complete picture.
Common Mistakes
❌ Excluding sales salaries
Many teams only count ad spend. A fully-loaded CAC must include sales rep salaries, commissions, sales tools, and even a portion of leadership time spent on deals.
❌ Mixing paid and organic
Blended CAC hides the true cost of paid acquisition. Calculate separate CACs for paid, organic, and referral channels to understand real unit economics per channel.
❌ Counting trial signups as customers
A trial user isn't a customer until they convert to paid. If you count trial signups, your CAC looks artificially low and masks a conversion problem.
Industry Benchmarks
| Category | Good | Average | Poor |
|---|---|---|---|
| B2B SaaS (SMB) | $200-500 | $500-1,500 | $1,500+ |
| B2B SaaS (Enterprise) | $2,000-5,000 | $5,000-15,000 | $15,000+ |
| B2C SaaS | $20-80 | $80-200 | $200+ |
Source: ProfitWell Subscription Benchmarks
Benchmark data sourced from ProfitWell Subscription Benchmarks.