Metrics · Finance · Monetization · Quarterly · months · Updated 2026-07-21

What is CAC Payback Period?

Short answer: The number of months required for a customer's gross margin to repay their acquisition cost.

Definition

The number of months required for a customer's gross margin to repay their acquisition cost.

Formula

CAC / (Monthly revenue per customer x Gross margin %)

How to measure

Divide CAC by the monthly gross profit generated per customer to find how many months of margin are needed to break even on acquisition.

Why track it

A shorter payback period frees up cash faster to reinvest in more acquisition, which matters most for cash-constrained early-stage companies.

Example

A $400 CAC against $80 in monthly gross profit per customer produces a 5-month payback period.

FAQ

What is CAC Payback Period?
The number of months required for a customer's gross margin to repay their acquisition cost.
How do you calculate CAC Payback Period?
CAC / (Monthly revenue per customer x Gross margin %)
Why track CAC Payback Period?
A shorter payback period frees up cash faster to reinvest in more acquisition, which matters most for cash-constrained early-stage companies.
What is CAC Payback Period? Definition, formula, and growth use · Cofounderbase