Not to be confused with Cost-Per-Acquisition, Cost-Per-Click, or Cost-Per-Lead-Generation, Cost-Per-Action (CPA) is a payment model that allows advertisers to pay marketing channels only for specific actions taken by customers (e.g., purchase, signup, link click).

The most basic formula for calculating the CPA is dividing the total marketing cost (month/year) by the total number of customers – the more marketing touchpoints are required before a conversion, the more expensive the acquisition. Cost-Per-Action can be improved by fine-tuning campaigns, increasing conversion rate (CRO), and setting additional goals beyond conversions like increasing the time that visitors spend on a website.