Know exactly what it costs to win one customer — the foundation of healthy unit economics.
What is customer acquisition cost (CAC)?
CAC is the total cost of winning one new customer. It's the denominator behind almost every growth decision, because if you don't know what a customer costs, you can't tell whether acquiring them is profitable.
CAC = Total sales & marketing cost ÷ New customers acquired
If you spent $30,000 on sales and marketing last quarter and gained 150 customers, your CAC is $30,000 ÷ 150 = $200.
What to include in "cost"
A fully-loaded CAC counts more than ad spend: include the salaries of your sales and marketing team, software and tools, agency and freelancer fees, and creative production. Many businesses understate CAC by only counting media spend — which makes campaigns look more profitable than they really are.
CAC only means something next to LTV
A $200 CAC is excellent if each customer is worth $900 over their lifetime, and disastrous if they're worth $150. That's why CAC is almost always read alongside lifetime value as the LTV:CAC ratio — the single clearest test of whether your growth engine is sustainable. To lower CAC, improve targeting, conversion rate, and retention (so referrals and repeat business reduce paid dependence).
Frequently asked questions
How do you calculate customer acquisition cost?
Divide your total sales and marketing spend over a period by the number of new customers acquired in that same period. For example, $30,000 spent to gain 150 customers is a CAC of $200.
What is the difference between CAC and CPA?
CPA (cost per acquisition) usually refers to the cost of a specific conversion action, like a lead or signup. CAC specifically measures the cost of a paying customer and typically includes fully-loaded costs like salaries and tools, not just ad spend.
What is a good CAC?
There is no universal number — a good CAC is one that is comfortably lower than the lifetime value of the customer it buys. Aim for an LTV:CAC ratio of around 3:1 or better rather than chasing an absolute CAC figure.
How can I reduce CAC?
Improve ad targeting and creative to cut wasted spend, raise landing-page conversion rates, and invest in retention and referrals so existing customers bring in new ones, reducing reliance on paid acquisition.
What costs should be included in CAC?
A fully-loaded CAC includes all sales and marketing spend: ad budgets, team salaries, software, agencies, and creative production. Counting only ad spend understates CAC and makes unit economics look better than they are.
How is CAC different from cost per lead?
Cost per lead (CPL) measures spend divided by leads generated. CAC measures spend divided by paying customers. CPL is earlier in the funnel; CAC is the number that matters for profitability because only customers generate revenue.