TLDR:
User Acquisition Cost (CAC) is the average cost a business incurs to acquire a single new customer, including marketing, sales, and onboarding expenses.
Calculating CAC
CAC = Total Sales & Marketing Costs ÷ Number of New Customers Acquired during the period. Costs include paid advertising, sales team salaries and commissions, marketing tools, content creation, and overhead allocated to customer acquisition. Best practice is to calculate CAC by channel (organic vs. paid, by campaign) and by customer segment to understand which acquisition methods are most efficient.
CAC Benchmarks
Healthy CAC depends on customer lifetime value (LTV). The LTV:CAC ratio should typically exceed 3:1 for SaaS businesses, with CAC payback period under 12-18 months for venture-backed companies. B2B SaaS companies often have higher CAC ($1,000-$10,000+) but compensate with higher LTV. Consumer products typically have lower CAC but also lower LTV.
Reducing CAC
Effective CAC reduction strategies include investing in product-led growth, building organic content channels, optimizing conversion funnels, leveraging referrals and word-of-mouth, refining target customer profiles, and improving sales efficiency. Sustainable businesses balance growth with unit economics — chasing growth at any CAC is a common path to startup failure.
UAC vs. CAC
User Acquisition Cost (UAC) and Customer Acquisition Cost (CAC) are related but distinct: UAC typically measures the cost of acquiring a registered user or active free user, while CAC measures the cost of acquiring a paying customer. The distinction matters for freemium business models where free users may eventually convert to paid plans — a low UAC may be misleading if free-to-paid conversion is poor. Sophisticated SaaS companies track both UAC and CAC, alongside conversion rates, to understand the full customer-acquisition funnel and identify optimization opportunities.