CPA (Cost Per Acquisition)
Also known as: Cost Per Acquisition, Cost Per Action
CPA is the average cost to acquire one paying customer (or completed action), calculated as spend divided by conversions.
What it actually means
Cost per acquisition measures what you pay for an actual outcome — a purchase, a booked appointment, a signed contract — rather than an intermediate step like a click or a lead. It is the truest efficiency metric because it accounts for everything that happens after the click, including how well your sales process converts leads into customers. CPA is sometimes called cost per action when the tracked event is a key step short of a sale. Because it depends on conversion tracking firing correctly, an inaccurate CPA almost always traces back to a broken pixel or missing Conversions API events rather than the ads themselves.
Spending $2,400 to win 30 new customers is an $80 CPA.
For a local business, CPA is the number to compare against profit per customer. If a new customer nets you $500 and your CPA is $120, every campaign dollar is multiplying.
Related terms
CPL is the average cost to generate one lead, calculated as total ad spend divided by the number of leads collected.
ROAS is the revenue generated for every dollar of ad spend, calculated as conversion revenue divided by ad spend.
LTV is the total revenue (or profit) a customer generates over the entire span of their relationship with your business.
CAC is the total cost to acquire one new customer, including ad spend and all sales and marketing expenses, divided by customers won.
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