CAC Payback Period vs LTV:CAC Ratio
Both metrics assess acquisition efficiency, but from different angles. CAC Payback Period measures how quickly you recover your acquisition spend; LTV:CAC measures the total value multiple you earn on that investment. Cash-constrained companies focus on payback; growth-stage investors focus on LTV:CAC.
At a Glance
CAC Payback Period
Months required to recover customer acquisition costs
LTV:CAC Ratio
Relationship between customer lifetime value and acquisition cost
Key Differences
- CAC Payback is measured in months; LTV:CAC is a dimensionless ratio.
- CAC Payback uses gross margin to determine recovery speed; LTV:CAC uses the full lifetime gross profit.
- A short payback period with a low LTV:CAC can indicate high early churn.
- Best-in-class SaaS targets CAC Payback < 12 months and LTV:CAC > 3.
When to Use Each
Use CAC Payback Period when…
Use CAC Payback Period when cash flow and runway are a concern. Shorter payback means you recycle capital faster and need less working capital to grow.
Full CAC Payback Period guide →Use LTV:CAC Ratio when…
Use LTV:CAC to assess the long-run return on your go-to-market investment and compare against the 3x industry benchmark.
Full LTV:CAC Ratio guide →Formulas
CAC PAYBACK PERIOD
CAC Payback Period = CAC / (Monthly ARPU × Gross Margin %)
CAC / Monthly Profit per CustomerLTV:CAC RATIO
LTV:CAC Ratio = Customer Lifetime Value / Customer Acquisition Cost
(Monthly ARPU × Gross Margin × Lifespan) / CACCharts
CAC Payback Period
LTV:CAC Ratio