Blended CAC: formula and example
Blended CAC divides total acquisition spend by all new customers. The formula, a worked example, and how it differs from paid CAC.
The short answer: blended customer acquisition cost (CAC) is your total sales and marketing spend divided by the number of new customers won in the same period, from every channel including organic and referrals. Paid CAC divides only paid spend by only the customers that came from paid. Blended CAC is harder to flatter, and paid CAC is more useful for channel decisions.
The formula
Blended CAC = total acquisition spend ÷ new customers
Decide once what counts as spend, and keep it the same each period: ad spend, agency or contractor fees, tools, and, if you want the full cost, the salaries of the people doing the acquiring. Count new customers for the same period.
A worked example (illustrative)
- Ad spend: $300K. Agency and tools: $60K. Total acquisition spend: $360K.
- New customers won in the period: 18, of which 9 came from paid campaigns and 9 from organic, referrals and direct.
- Blended CAC = $360K ÷ 18 = $20K.
- Paid CAC = $300K ÷ 9 = $33.3K, if you attribute all the ad spend to the 9 paid customers.
Both are true. Blended CAC shows what a customer costs the business. Paid CAC shows what the ads cost per customer they brought in. The gap between them is the work organic and referrals are doing.
How to use it
- Track blended CAC over time to see whether acquisition is getting more or less efficient overall.
- Use paid CAC by channel to decide where to put budget, using the CRM to count customers by source.
- Compare CAC with the time it takes to earn it back. See CAC payback and LTV:CAC, explained.
Common traps
- Counting leads or opportunities as customers.
- Leaving out agency fees or salaries in some periods and including them in others.
- Ignoring the sales cycle. In B2B, this month's spend wins customers months later, so compare against a lagged period or a rolling average.
- Crediting paid with customers the CRM shows came from elsewhere. See why your ad platforms do not agree with your CRM.
Work it out with your own numbers in the CAC calculator.
Questions people ask
What is blended CAC?
Total acquisition spend divided by all new customers in the same period, from every channel, including organic and referrals.
What is the difference between blended CAC and paid CAC?
Blended CAC uses all spend and all customers. Paid CAC uses only paid spend and only the customers that came from paid channels.
Is a lower blended CAC always better?
Not always. It matters alongside the value of the customer and how fast the cost is earned back, so read it together with LTV and payback.
What should I include in CAC?
Choose one definition and keep it constant: typically ad spend, agency and tool costs, and optionally the salaries of the sales and marketing team.
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