What is CAC (Customer Acquisition Cost)? (Definition + SaaS example)
Customer Acquisition Cost (CAC) is the total cost of acquiring a new customer, calculated by dividing total sales and marketing spend by the number of new customers acquired in a period. CAC is one of the most critical SaaS unit economics metrics, determining how efficiently a company converts spend into paying customers.
Formula and Calculation
Customer Acquisition Cost
CAC = (Total Sales Spend + Total Marketing Spend) ÷ New Customers Acquired
For a more detailed breakdown:
Fully Loaded CAC
Fully Loaded CAC = (Sales Salaries + Commissions + Marketing Spend + Tools + Overhead) ÷ New Customers
Worked SaaS Example
A B2B SaaS company tracks its Q1 acquisition spend and results:
| Cost Category | Q1 Amount |
|---|---|
| Sales team salaries & commissions | $180,000 |
| Paid advertising (Google, LinkedIn) | $65,000 |
| Content & events marketing | $35,000 |
| Sales tools (CRM, outreach) | $12,000 |
| Marketing tools (analytics, automation) | $8,000 |
| Total Sales & Marketing | $300,000 |
New customers acquired in Q1: 40
| Metric | Value |
|---|---|
| Blended CAC | $300,000 ÷ 40 = $7,500 |
| Paid-only CAC (25 customers from paid) | $65,000 ÷ 25 = $2,600 |
| Organic CAC (15 customers from inbound) | $235,000 ÷ 15 = $15,667 |
The blended CAC is $7,500, but the channel mix reveals that paid acquisition is significantly more efficient per customer. However, organic customers may have higher LTV — the full picture requires LTV:CAC analysis by channel.
CAC Benchmarks by Segment
| Segment | Typical CAC | Typical ACV | Target LTV:CAC |
|---|---|---|---|
| Self-serve SMB | $100–$500 | $1,200–$5,000 | 3:1+ |
| Mid-market | $2,000–$15,000 | $12,000–$50,000 | 3:1+ |
| Enterprise | $10,000–$100,000 | $50,000–$500,000+ | 3:1+ |
Why CAC Matters for SaaS
Finance teams use CAC to measure the efficiency of the go-to-market engine. A rising CAC without a corresponding increase in customer quality or LTV signals that growth is becoming less efficient — a leading indicator of future profitability challenges.
In investor reporting, CAC is always presented alongside LTV and payback period. Investors look for evidence that the company can acquire customers profitably and that the economics improve at scale. A declining CAC-to-revenue ratio as the company grows is a strong positive signal.
A common mistake is underloading CAC by excluding significant costs. Leaving out sales team salaries, tools, or overhead makes CAC look artificially low and the LTV:CAC ratio artificially attractive. Investors will recalculate using fully loaded costs — discrepancies erode trust.
CAC connects directly to LTV through the LTV:CAC ratio, the most important unit economics metric in SaaS. It also determines the payback period — how many months of gross profit it takes to recover the acquisition investment.
Calculate and track your CAC in JustPaid
Frequently Asked Questions
CAC should include all costs directly tied to acquiring new customers: sales team salaries and commissions, marketing spend (ads, content, events), sales tools and software, and a proportional share of overhead for the sales and marketing teams. Exclude customer success and support costs — those are retention costs, not acquisition costs.
Related Terms
LTV (Customer Lifetime Value)
Customer Lifetime Value (LTV) is the total revenue a SaaS company expects to earn from a single customer over the entire duration of their relationship. LTV combines average revenue per user, gross margin, and churn rate to quantify the long-term economic value of each customer.
LTV:CAC Ratio
The LTV:CAC ratio compares Customer Lifetime Value to Customer Acquisition Cost, measuring how much long-term value each acquisition dollar generates. A ratio of 3:1 or higher is the standard SaaS benchmark — meaning every dollar spent on acquisition returns at least three dollars in gross profit over the customer's lifetime.
CAC Payback Period
CAC payback period is the number of months it takes for a customer's gross profit to repay the cost of acquiring them. In SaaS, a payback period under 12 months is considered efficient — meaning the company recovers its acquisition investment within the first year and every subsequent month generates pure profit.
