# What is the CAC payback period?

> CAC payback period is how many months it takes a new customer to earn back what you paid to win them. Formula and a worked example in rupees.
- **Author**: Marxx
- **Published**: 2026-10-23
- **Category**: Metrics
- **URL**: https://marxx.ai/library-glossary/cac-payback-period

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CAC payback period is the number of months it takes a new customer to earn back the cost of winning them. If a customer cost INR 1,200 to acquire and brings in INR 300 of profit a month, they pay you back in four months.

## The formula

CAC payback (months) = CAC / monthly gross profit per customer

Use profit, not revenue, or the payback looks faster than it is.

## A worked example

Say a meal-kit subscription has these numbers:

- CAC: INR 2,400
- Monthly plan: INR 1,500, with a 30% gross margin, so INR 450 profit a month
- Payback = 2,400 / 450 = **5.3 months**

Now the same brand improves its ads and cuts CAC to INR 1,800. Payback drops to 4 months. That frees cash to win the next customer sooner.

## Why it matters

- **Cash.** Until a customer pays back, you are funding them. Fast payback means growth funds itself.
- **Risk.** If customers cancel in month four and payback is month five, every customer loses money.
- **Spend decisions.** A channel with a higher CAC can still be fine if its customers pay back faster.

## For one-off purchases

If customers buy once, payback is the first order. The first order's profit has to cover CAC, or you need repeat orders to make it work. Track how many customers return within 90 days.

## FAQ

### What is a good CAC payback period?

Shorter is safer. If customers buy one product at a time, aim to recover CAC on the first or second order. A subscription can accept longer, if customers stay that long.

### How does it relate to LTV:CAC?

[LTV:CAC](/glossary/ltv-to-cac-ratio) says how much you earn back in total. Payback says how fast. A business needs both to look healthy.

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