What is customer acquisition cost?
Also known as: CAC
Customer acquisition cost (CAC) is the total sales and marketing expense required to acquire one new customer over a given period. It is used alongside customer lifetime value to judge whether growth is economically sustainable.
Formula
How to calculate customer acquisition cost
CAC = Total sales and marketing spend ÷ New customers acquired- Total sales and marketing spend
- Fully loaded: salaries, commissions, advertising, tooling, events, and overhead
- New customers acquired
- Customers acquired in the same period the spend occurred
Worked example
You spend $400,000 on sales and marketing in a quarter and acquire 50 customers. CAC = $400,000 ÷ 50 = $8,000.
Benchmarks
Typical customer acquisition cost ranges
Commonly reported ranges for B2B SaaS. Treat these as orientation — your own segment and contract structure matter more than any cross-industry figure.
| Segment | Typical range |
|---|---|
| Healthy LTV:CAC ratio | 3:1 or better |
| Healthy CAC payback (B2B SaaS) | Under 12 months |
| Concerning CAC payback | Over 18–24 months |
In practice
What you need to know about customer acquisition cost
Fully loaded, or the number is fiction
The most common way CAC gets understated is by counting only advertising spend and omitting salaries, commissions, sales tooling, events, and marketing overhead. Since people are usually the largest cost in B2B acquisition, an ad-only CAC can understate the true figure several times over and will justify spend that is actually unprofitable.
The attribution lag problem
Dividing this quarter's spend by this quarter's customers assumes acquisition is instantaneous. With a six-month sales cycle, the customers closing now were generated by spend two quarters ago. In a business with rapidly changing spend, this mismatch distorts CAC badly — lag the spend to match your average sales cycle, or measure by cohort.
Blended CAC hides everything useful
A single company-wide CAC averages a $400 self-serve signup with a $60,000 enterprise deal. Segment by channel and customer type, because the decision CAC informs — where to spend the next marginal dollar — is always segment-specific. Blended CAC can look healthy while your fastest-growing channel loses money.
CAC payback often matters more than the ratio
LTV:CAC tells you whether a customer is eventually profitable. CAC payback tells you how long your cash is tied up, which is what actually constrains growth for a company that is not capital-rich. A 3:1 ratio with 30-month payback can be unfundable even though the unit economics look fine.
How to improve it
Improving customer acquisition cost
Include every cost, then segment
Fully loaded spend divided by segment-specific acquisition. Both steps are needed; either alone misleads.
Report payback period alongside the ratio
Payback governs cash constraints, which is usually the binding limit on growth rate.
Lag spend to match the sales cycle
Attribute spend to the period that generated the pipeline, not the period the deal closed.
FAQ
Customer acquisition cost questions, answered
How do you calculate customer acquisition cost?+
Divide fully loaded sales and marketing spend by the number of new customers acquired in the same period. Fully loaded means salaries, commissions, advertising, tooling, events, and overhead — omitting people costs is the most common error and materially understates CAC.
What is a good CAC payback period?+
Under 12 months is generally considered healthy for B2B SaaS. Beyond 18–24 months, growth becomes heavily dependent on external capital because cash is tied up too long to reinvest. Payback often constrains growth more than the LTV:CAC ratio does.
What is a good LTV to CAC ratio?+
3:1 is the standard benchmark. Below 1:1 you lose money on every customer. Above 5:1 often indicates under-investment — you could likely spend more acquiring customers and remain profitable.
Should customer success costs be included in CAC?+
No. CAC covers acquiring the customer; post-sale customer success is a cost of retaining and serving them, and belongs in cost of goods sold or a separate retention cost line. Including it conflates acquisition efficiency with service efficiency.
Related terms
Keep reading
Customer lifetime value
Customer lifetime value (CLV) is the total gross profit a business expects to earn from a customer over the entire course of the relationship. It is used to decide how much can profitably be spent acquiring and retaining customers.
Churn rate
Churn rate is the percentage of customers who stop paying for a product during a given period. It is calculated by dividing the number of customers lost during the period by the number of customers at the start of that period.
Monthly recurring revenue
Monthly recurring revenue (MRR) is the predictable revenue a subscription business expects to receive every month, normalized to a monthly figure. It excludes one-time charges such as setup fees, professional services, and overages.
Net revenue retention
Net revenue retention (NRR) is the percentage of recurring revenue retained from existing customers over a period, including expansion, contraction, and churn, but excluding new customer revenue. NRR above 100% means existing customers grew enough to more than offset all losses.
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