SaaS Metric
LTV:CAC Ratio (LTV:CAC)
Definition
The LTV:CAC ratio compares how much a customer is worth over their lifetime (LTV) to what it costs to acquire them (CAC). LTV:CAC = customer lifetime value ÷ customer acquisition cost. A ratio around 3:1 is the common rule of thumb for healthy unit economics; below 1:1 you lose money on every customer, while a very high ratio (5:1+) often means you are under-investing in growth.
Formula
LTV:CAC ratio = customer lifetime value (LTV) ÷ customer acquisition cost (CAC)
Benchmark
A ratio near 3:1 is the widely cited target for healthy SaaS unit economics. Below ~1:1 is unsustainable; consistently above ~5:1 can signal underspending on acquisition.
Why the ratio matters more than either number alone
LTV and CAC are only meaningful in relation to each other. A high CAC is fine if customers are worth far more over their lifetime; a low CAC is dangerous if those customers churn quickly. The ratio captures whether your go-to-market motion creates more value than it consumes.
Because LTV depends directly on retention, the fastest lever on LTV:CAC for most SaaS is usually churn, not acquisition cost. Reducing churn lengthens the average customer lifetime, which raises LTV and the ratio without spending an extra dollar on sales or marketing.
Reading high and low ratios
A ratio below 1:1 means you spend more to acquire a customer than you ever earn back — unsustainable without changing pricing, retention, or acquisition efficiency. Around 3:1 is the conventional healthy zone. A ratio far above 5:1 is not automatically good: it often means you could acquire more customers profitably and are leaving growth on the table by underspending.
Frequently asked questions
What is a good LTV:CAC ratio?
Around 3:1 is the common rule of thumb for healthy SaaS unit economics — three dollars of lifetime value for every dollar of acquisition cost. Below 1:1 is unsustainable, and consistently above 5:1 often signals you are underspending on growth.
How do you calculate LTV:CAC?
Divide customer lifetime value (LTV) by customer acquisition cost (CAC). LTV is typically average revenue per account × gross margin ÷ churn rate; CAC is total sales and marketing spend ÷ new customers acquired in the same period.
How do you improve the LTV:CAC ratio?
You can raise LTV (reduce churn, increase expansion revenue, improve gross margin or pricing) or lower CAC (more efficient channels, better targeting, higher conversion). For most SaaS, cutting churn is the highest-leverage move because it compounds into a longer customer lifetime.
Related metrics
Customer Lifetime Value (LTV)
Customer lifetime value (LTV) estimates the gross-margin revenue an average customer generates before churning. Learn the margin-adjusted LTV formula, the LTV:CAC ratio, and benchmarks.
Customer Acquisition Cost (CAC)
Customer acquisition cost (CAC) is the fully loaded sales and marketing spend to win one customer. Learn the CAC formula, the LTV:CAC ratio, and healthy SaaS benchmarks.
CAC Payback Period
CAC payback period is how many months of gross margin it takes to recoup the cost of acquiring a customer. Learn the formula and healthy SaaS benchmarks.
Churn Rate
Churn rate is the percentage of customers or revenue lost in a period. Learn the customer churn and revenue churn formulas, healthy SaaS benchmarks, and how to reduce it.
Track this automatically
Connect Stripe and RetentionLens computes LTV:CAC for you — with cohorts, trends and churn-risk scoring. Start on the free tier.
Benchmarks are general SaaS ranges and vary by segment, stage and business model. Last reviewed 2026-05-30.