What is CAC? Customer acquisition cost explained

CAC (customer acquisition cost) is the total cost of acquiring one new customer, including ad spend and other marketing costs.

How is CAC calculated?

CAC = total acquisition spend ÷ new customers acquired

Example

Spending $12,000 on marketing in a month that brings 300 new customers gives a CAC of $40.

Why does CAC matter for e-commerce?

Comparing CAC with LTV (the LTV:CAC ratio) shows whether growth is sustainable. Unlike CPA, CAC counts only new customers.

How does Posta use CAC?

Posta's agents use CAC when reviewing your accounts and recommending changes. See the AI marketing analytics page for how it fits into your workflow.