What Is Cost Per Acquisition (CPA)?
The total cost to acquire one paying customer through marketing and sales.
Cost Per Acquisition (CPA) measures the total marketing and sales cost to convert a prospect into a paying customer. It goes further than CPL by accounting for every expense along the funnel, from the first ad click to the signed contract.
CPA is calculated by dividing total campaign or channel spend by the number of customers acquired. For demand gen teams, this is the metric that connects marketing investment to business outcomes. A CMO does not care about your CPL if the CPA makes the unit economics unsustainable.
Tracking CPA requires closed-loop attribution, meaning you need to connect the lead source all the way through to the closed deal in your CRM. This is where most teams struggle. Without accurate attribution, CPA is a guess.
Example: A demand gen team spends $50,000 on Google Ads over a quarter. Those ads generate 200 leads, 40 become MQLs, 10 become SQLs, and 3 close as customers. The CPA is $50,000 / 3 = $16,667 per customer. If the average contract value is $80,000, that CPA works. If ACV is $15,000, the channel is unprofitable.
Frequently Asked Questions
How is CPA different from CAC?
CPA usually refers to the cost of a specific campaign or channel to acquire a customer. CAC (Customer Acquisition Cost) includes all sales and marketing expenses divided by total new customers. CAC is the company-level metric; CPA is campaign-level.
What is a good CPA in B2B SaaS?
A common benchmark is that CPA should be less than one-third of the customer lifetime value (LTV). So if your average customer is worth $90,000 over their lifetime, your target CPA should be under $30,000.