TL;DR

The LTV:CAC ratio measures the return on customer acquisition investment. A ratio of 3:1 is the minimum benchmark for a scalable SaaS business; 5:1+ is strong. Companies below 3:1 are destroying value with every customer they acquire.

The LTV:CAC Formula

LTV = (Average Revenue per Customer per Month × Gross Margin %) ÷ Monthly Churn Rate

LTV:CAC Ratio = LTV ÷ CAC

Example:

  • - Average MRR per customer: $1,000
  • Gross margin: 75%
  • Monthly churn: 2%
    • LTV = ($1,000 × 75%) ÷ 2% = $37,500
    • CAC: $10,000 | LTV:CAC = 3.75:1

    Benchmarks

    less than 1:1: Destroying value — stop scaling

    1:1 – 3:1: Below benchmark — improve before scaling

    3:1: Minimum viable for scaling

    5:1+: Strong — scale aggressively

    10:1+: Exceptional — may be underinvesting in growth

    The CAC Payback Period

    CAC Payback = CAC ÷ (Monthly Revenue per Customer × Gross Margin %)

    Example: $10,000 ÷ ($1,000 × 75%) = 13.3 months

    Benchmark: less than 12 months is strong. 12–18 months is acceptable. Greater than 24 months is problematic

    How to Improve LTV:CAC

    Increase LTV: Reduce churn (most impactful), increase expansion revenue, increase ACV, improve gross margins

    Reduce CAC: Improve lead quality, invest in inbound, improve conversion rates, build referral programs

    Key Takeaways

    Key Takeaways
    • LTV:CAC of 3:1 is the minimum benchmark; 5:1+ is strong.
    • LTV = (MRR × Gross Margin) ÷ Monthly Churn Rate.
    • Churn has an exponential effect on LTV — reducing churn is the highest-leverage lever.
    • CAC payback less than 12 months is strong; greater than 24 months is problematic.
    • Companies below 3:1 LTV:CAC are destroying value with every customer acquired.