What Is Customer Acquisition Cost? Definition & Guide

Customer acquisition cost (CAC) is the total cost of acquiring a new customer, calculated by dividing total sales and marketing spend over a given period by the number of new customers acquired in that same period. It is one of the most fundamental unit economics metrics for any business -- telling you how much it costs, on average, to turn a prospect into a paying customer. Managing CAC effectively is central to building a sustainable, profitable marketing program.

Why Customer Acquisition Cost Matters

CAC determines whether a business model is viable. If it costs more to acquire a customer than that customer is worth over their lifetime (lifetime value, or LTV), the business is unsustainable. The relationship between LTV and CAC -- typically expressed as the LTV:CAC ratio -- is one of the most important health indicators for any growth-stage company.

For marketing teams, CAC provides a clear benchmark for evaluating channel and program efficiency. If your blended CAC is $1,000 and one channel acquires customers at $500 while another acquires them at $3,000, that difference should drive investment decisions. Without tracking CAC by channel, these decisions get made on impressions and intuition rather than economics.

Content marketing's distinctive strength is its impact on CAC over time. Organic content generates leads without ongoing variable cost -- once a piece of content ranks, it drives leads essentially for free. As your content library grows, the cost per lead from organic channels decreases, pulling blended CAC down. This dynamic is one of the most compelling economic arguments for investing in content.

How It Works

Calculating CAC requires clean attribution between marketing spend and new customer acquisition. Total sales and marketing costs -- including salaries, tools, ad spend, agency fees, and content production costs -- are summed for the period and divided by the number of new customers acquired. The result is the average cost to acquire one customer.

More granular analysis breaks CAC down by channel: what does it cost to acquire a customer from paid search versus organic content versus outbound sales? This channel-level view identifies where CAC is most efficient and where it is eating into margin.

Improving CAC involves either reducing acquisition costs (better content efficiency, lower CPCs, more organic traffic) or improving conversion rates (better landing pages, stronger offers, more relevant content). Content marketing works on both levers simultaneously. Averi helps teams produce content more efficiently -- reducing the cost per piece and the cost per acquired lead -- while also improving content quality and conversion performance.

Customer Acquisition Cost Best Practices

• Calculate CAC regularly -- at least quarterly -- by total and by channel
• Include all relevant costs in CAC calculation: headcount, tools, agency fees, and ad spend
• Track CAC trends over time -- a rising CAC is a signal that something in the acquisition process is deteriorating
• Benchmark your LTV:CAC ratio against your industry -- a 3:1 ratio is often cited as a healthy minimum
• Identify which content pieces contribute most to pipeline and reduce CAC, and prioritize more of that type
• Use CAC data to make the case for content marketing investment -- demonstrating falling CAC from organic channels is compelling

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