What is Payback Period?

CAC Payback Period is the number of months it takes for a newly acquired customer’s contribution margin to equal the cost of acquiring them. It’s a critical cash flow metric that determines how quickly you can reinvest in growth.

Why It Matters

Even if your LTV:CAC ratio is healthy (3:1+), a long payback period can kill a fast-growing brand by creating a cash flow crunch. The shorter your payback, the faster you can reinvest profits into further growth.

How to Calculate It

Payback Period = CAC ÷ (Monthly Revenue Per Customer × Contribution Margin %)

If CAC is $60, monthly revenue per customer is $30, and contribution margin is 50%:

Payback = $60 ÷ ($30 × 0.5) = 4 months

Benchmarks

< 3 months: Excellent — you can scale aggressively
3-6 months: Healthy — standard for most DTC brands
6-12 months: Manageable, but limits growth pace
12+ months: Dangerous — requires external funding to scale

Payback by Channel

Track payback period per acquisition channel. A channel with lower ROAS but faster payback may be better for your cash flow than one with higher ROAS but slower payback.