What Is Customer Acquisition Cost (CAC)?
What CAC means and how to calculate it
CAC is the average cost of winning one new customer. You calculate it by taking everything you spent on sales and marketing across a defined period and dividing it by the number of new customers acquired in that same period.
The two halves of the fraction must cover the same time window. If you put a quarter of spend over the numerator, count the customers won in that quarter underneath it. Mismatching the periods (for example, comparing this month's spend to customers who actually signed up months later) is the most common way CAC gets quietly distorted.
Why marketers track it
CAC turns a sprawling budget into a single per-customer number you can compare across channels, campaigns, and quarters. It is one half of the most important unit-economics check in marketing: how much a customer costs to acquire versus how much they are worth over their lifetime. On its own CAC is just a cost; paired with lifetime value it tells you whether growth is profitable.
What to include in the cost
Include every cost that exists to acquire customers, not just the ad bill. A defensible CAC is "fully loaded": it captures media spend plus the people, tools, and overhead that turn that spend into closed business. Leaving costs out makes CAC look artificially low and makes the number useless for comparison.
Costs to count
- Paid media: ad spend across search, social, display, and any paid placements.
- Salaries & commissions: the loaded cost of the marketing and sales teams who acquire customers.
- Tools & software: your CRM, marketing automation, analytics, and ad-management subscriptions.
- Agencies & contractors: outsourced creative, media buying, and freelance support.
- Content & creative production: the cost of producing the assets that drive acquisition.
What to leave out
Exclude spend aimed at existing customers, since retention, success, and expansion costs belong to a different metric. Also leave out one-off, non-acquisition expenses and the cost of fulfilling or servicing the product. The point of CAC is to isolate the cost of getting a customer, not keeping or serving one.
Blended CAC vs paid CAC
Blended CAC divides all acquisition spend by every new customer, including organic and referral wins; paid CAC counts only the customers won through paid channels against paid spend alone. Both are valid. They answer different questions, and reporting one as if it were the other is misleading.
| Metric | Numerator (cost) | Denominator (customers) | Best for |
|---|---|---|---|
| Blended CAC | All sales & marketing spend | All new customers (paid + organic + referral) | Overall business efficiency |
| Paid CAC | Paid channel spend only | Customers attributed to paid channels | Deciding whether to scale paid spend |
Verdict: use blended CAC to report the true, all-in cost of growth to leadership, and use paid CAC to decide whether to pour more money into ads. Blended CAC looks better because free organic customers drag the average down, so never use it to justify scaling a paid channel. When you cite a number, always say which one it is.
A worked example
Suppose that in Q2 your team spent $120,000 on sales and marketing ($70,000 on paid ads, $40,000 in loaded salaries, and $10,000 on tools and agencies) and acquired 200 new customers in the same quarter.
Now split the channels. If 140 of those customers came from paid ads and you spent $70,000 on that media, your paid CAC is $70,000 ÷ 140 = $500. The remaining 60 customers arrived organically at little marginal cost, which is exactly why the blended figure of $600 understates how expensive your paid growth really is. The two numbers, side by side, are far more useful than either alone.
Why CAC only matters in context
A CAC number means nothing on its own. It only becomes useful next to the value each customer returns. A $5,000 CAC is excellent if those customers stay for years and spend tens of thousands; a $50 CAC is a disaster if they churn after one cheap purchase. Always pair CAC with lifetime value.
The two checks marketers lean on most are the LTV-to-CAC ratio and the CAC payback period. A common rule of thumb is an LTV:CAC ratio of around 3:1 or better, enough margin to cover overhead and turn a profit, alongside a payback period under roughly 12 months, meaning you recover the acquisition cost within a year. Both vary widely by business model, contract length, and margin, so treat them as directional guardrails rather than hard targets.
Frequently asked questions
What is the formula for CAC?
CAC equals the total sales and marketing cost over a period divided by the number of new customers acquired in that same period. If you spent 50,000 on sales and marketing in a quarter and won 100 new customers, your CAC is 500. Always match the spend window to the customers it produced.
What's the difference between blended and paid CAC?
Blended CAC divides total acquisition spend by every new customer, including those from organic and referral channels. Paid CAC counts only customers won through paid channels, divided by paid spend. Blended flatters performance; paid CAC tells you the true cost of buying growth.
Should salaries be included in CAC?
Yes. A fully loaded CAC includes the salaries, commissions, and overhead of the sales and marketing people who win customers, alongside ad spend and tooling. Ad-only CAC understates the real cost. Be explicit about which version you report so comparisons stay honest.
What is a good CAC?
There is no universal good number. CAC only makes sense against the value a customer returns. The common benchmark is an LTV-to-CAC ratio of roughly 3:1 or higher, plus a CAC payback period under about 12 months. A high CAC is fine if customers stay long and spend a lot.
Last updated: 14 June 2026