---
title: "What Is CAC? Definition and PM Examples"
description: "Customer acquisition cost, or CAC, is total sales and marketing spend divided by new customers won. See the formula, an example, how the bootcamp teaches it."
canonical_url: "https://builderscamp.com/guides/glossary/customer-acquisition-cost"
date_published: "2026-09-16"
date_modified: "2026-09-16"
author: "Andre Albuquerque"
publisher: "Builders Camp"
guide_class: "glossary"
---

# What Is CAC?

**TL;DR:** Customer acquisition cost, or CAC, is the average total cost of acquiring one new paying customer, calculated as total sales and marketing spend divided by new customers won in a period. A lower CAC generally signals stronger product-market fit and more efficient marketing and sales.

## What does CAC mean?

Customer acquisition cost, or CAC, is a business metric that measures the average total cost of acquiring one new paying customer, including all sales and marketing expenses over a given period. Per [Wall Street Prep](https://www.wallstreetprep.com/knowledge/customer-acquisition-cost-cac/), the formula is total sales and marketing costs divided by the number of new customers acquired in that same period, and a lower CAC generally implies solid product-market fit and effective marketing and sales execution, while a rising CAC can signal saturation in a channel or weakening product-market fit.

CAC deliberately excludes repeat customers and retention spend, which is what separates it cleanly from the broader cost of running a go-to-market motion.

## Why CAC matters for product managers

Business for Product Managers treats CAC as one of the core unit economics numbers a PM needs fluency in, paired directly with [customer lifetime value](https://builderscamp.com/guides/glossary/customer-lifetime-value) in the same module. The bootcamp's own materials describe unit economics literacy, including CAC, margins, and payback, as what lets a PM evaluate a product bet with ROI thinking instead of gut feel.

The bootcamp also teaches CAC in the context of business case review, since an optimistic assumption about how easily a feature will reduce CAC or improve conversion is exactly the kind of number that needs scrutiny before it reaches a CFO.

## CAC example

In Business for Product Managers' practical challenge, a PM reviews a business case for an AI feature at Cascade, a B2B SaaS company with 850 existing customers at an average annual contract value of 14,100 dollars. While the case centers on churn and expansion assumptions rather than new customer CAC directly, the same rigor the bootcamp teaches for auditing those numbers, checking every assumption against what would actually have to be true, applies just as directly to a CAC figure used in any acquisition-focused business case.

A PM proposing a paid acquisition push, for instance, would need to show CAC alongside expected conversion and lifetime value before a finance partner would treat the investment as sound, exactly the kind of grounded, number first argument the bootcamp's practical challenge rewards.

## How Builders Camp teaches CAC

Builders Camp teaches customer acquisition cost inside the [Business for Product Managers bootcamp](https://builderscamp.com/bootcamps/business-for-product-managers), directed by Andre Albuquerque, as part of its unit economics module covering CAC, LTV, margins, and payback together.

Builders Camp runs live and self-paced bootcamps in product management and AI product building. [See the Business for Product Managers bootcamp](https://builderscamp.com/bootcamps/business-for-product-managers) for the next cohort dates.

## Frequently asked questions

### How do you calculate CAC?

Add total sales and marketing costs for a period, then divide by the number of new customers acquired in that same period. Spending 50,000 dollars to acquire 100 customers gives a CAC of 500 dollars.

### Does CAC include the cost of retaining existing customers?

No. CAC specifically excludes repeat customers and retention spend; it only accounts for the cost of winning genuinely new customers.

### What is a healthy CAC?

It depends entirely on the customer's lifetime value and the business model, so CAC is almost always read alongside LTV rather than judged as a standalone number.

### Can CAC change significantly between channels?

Yes, often dramatically. Paid acquisition channels tend to carry a higher CAC than organic or referral channels, which is why a monetization model has to match the acquisition channel bringing users in.

### What happens if CAC rises faster than LTV?

The unit economics start to break down, since the business is spending more to acquire each customer than that customer is worth over time, which is unsustainable without a change to pricing, retention, or acquisition strategy.

### Is CAC useful without a payback period calculation?

Less useful on its own. Pairing CAC with a payback period shows not just how much it costs to acquire a customer, but how long it takes to earn that cost back.

## Sources

- [Wall Street Prep: Customer Acquisition Cost (CAC), Formula and Calculator](https://www.wallstreetprep.com/knowledge/customer-acquisition-cost-cac/)

## How this guide was made

Researched from Builders Camp's bootcamp, track and masterclass material and the sources listed on this page, drafted with AI, and fact-checked against every source cited.