CAC Payback Period · The Speed of Capital Recovery
How long it takes for a customer's gross profit to repay the cost to acquire them. The math, the healthy thresholds by business type, and why payback period matters as much as LTV:CAC ratio for capital efficiency.
Attribution. CAC payback period is standard SaaS finance methodology, formalized in David Skok's SaaS metrics work and the SaaS Capital and OpenView annual benchmark reports. This article synthesizes the field.
What CAC payback measures
CAC payback period is the number of months it takes for a new customer's cumulative gross profit to equal the cost of acquiring them. Shorter is better — it means capital cycles faster and growth requires less working capital.
Company A cycles capital twice a year. Company B needs 3 years of cash to fund growth before any customer breaks even. The same ratio, completely different financing requirements.
Payback period determines how much capital you need to scale at a given rate. Slower payback = more working capital required = more dilution or debt.
The 12-month rule of thumb for SaaS. Most VCs use 12-month CAC payback as the line between healthy and concerning for SaaS. Above 12 months, the company needs continuous capital infusion to grow. Below 12 months, growth is self-funding.