Customer Acquisition Cost (CAC)

Customer Acquisition Cost (CAC) measures how much a business spends to win each new customer. The basic formula is: CAC = Total Sales & Marketing Spend / Number of New Customers Acquired. If a company spends $100,000 on sales and marketing in a month and acquires 200 new customers, the CAC is $500 per customer.

A more complete CAC calculation includes all costs associated with acquisition: paid advertising, content creation, sales team salaries and commissions, marketing tools and software, events, partnerships, and any onboarding costs that are required to activate a new customer. Some businesses separate "blended CAC" (all customers including organic) from "paid CAC" (only customers from paid channels).

CAC is most meaningful when compared to LTV through the LTV:CAC ratio. Healthy SaaS businesses target a ratio of 3:1 or higher, meaning each customer generates at least three times what it cost to acquire them. A ratio below 1:1 means the business is spending more to acquire customers than they will ever return — an unsustainable situation. The CAC payback period (months until the customer's revenue covers the acquisition cost) is another important related metric, with 12 months or less being the typical benchmark.

CAC tends to increase as a company scales. Early adopters are often easier and cheaper to acquire. As the addressable market expands, acquisition costs rise because the company must reach less aware, less motivated prospects. This dynamic makes retention increasingly important over time — it becomes more efficient to keep existing customers than to replace them.

This is where payment recovery becomes a unit economics story. Every involuntarily churned customer must be replaced at full CAC. LostChurn's payment recovery lets you retain customers you have already paid to acquire, directly improving your effective CAC and accelerating payback periods.