What Is a Good LTV:CAC Ratio?

Three times is the long-standing rule of thumb, and it survives because it is roughly where a business can grow without every new customer being financed from the bank account. Below it, the unit economics are marginal; far above it, the usual explanation is that acquisition is starved, not that the business is unusually efficient.

The honest reading depends on stage and segment:

• Early-stage B2B SaaS commonly lands at 2.5x–3x. The customer base is small and one churned account moves the number, so read the trend rather than a single month.
• Growth-stage B2B SaaS is expected to show 3x–4x, with 5x+ as best-in-class.
• Enterprise SaaS can justify 3x–5x because contracts are long and retention is high, but CAC is lumpy and should be measured on a rolling twelve months.
• Marketplaces and consumer subscriptions sit lower, often 2x–3x, because churn compresses lifetime; payback speed matters more than the ratio there.

If your number is far outside these ranges, the first suspicion should be the calculation, not the business.

The conventional formula is:

LTV   = ARPU × gross margin × (1 / monthly churn)
ratio = LTV / CAC

The gross margin term is not a refinement — it is the difference between profit and revenue. At an 80% gross margin, a shortcut that uses ARPU directly overstates LTV by 25%: a real 3.2x ratio is reported as 4x. At a 50% margin it doubles the ratio. Two companies with identical economics can appear to have completely different unit economics purely because one of them skipped this line.

Gross margin should include the cost of delivering the service — hosting, support, third-party APIs, payment processing — but not sales and marketing, which is already in CAC.

These ranges reflect commonly cited venture and operator guidance rather than a single proprietary dataset. Treat them as orientation, not as targets set by a standards body.

A blended figure across segments is close to meaningless: it averages a 6x enterprise cohort with a 2x self-serve cohort and describes neither. Segment by plan and by acquisition channel before drawing a conclusion.

Only four inputs matter, and retention is usually the cheapest to change:

• Churn. Lifetime is 1 ÷ monthly churn, so moving from 3% to 2% takes the average lifetime from about 33 months to 50 — roughly a 50% increase in LTV at constant ARPU. No additional acquisition spend is required.
• Gross margin. A five-point margin improvement flows straight through to LTV, and it is often available from infrastructure or support costs rather than price.
• ARPU. Pricing and packaging changes raise LTV but can also raise churn; the two effects have to be measured together.
• CAC. Channel mix is the lever. A blended CAC hides the fact that one channel may be at 1.5x and another at 6x; split the calculation by channel before cutting spend.

The 3x line assumes a mostly self-funding growth model. It is a poor target in three cases:

• Long payback. A 4x ratio with a 30-month payback still drains cash every time you grow. Read the CAC payback period alongside the ratio; a good ratio with slow payback is a financing problem, not a success.
• Early pre-product-market-fit. A 2x ratio on ten customers is noise. The number becomes decision-grade only when the cohort is large enough for churn to be stable.
• Deliberate land-and-expand. Some enterprise models start below 3x on the first contract and rely on expansion; the ratio on first-year revenue understates the eventual value, and the expansion assumption needs to be evidenced rather than hoped for.

• Using revenue instead of gross profit. The single largest error; it overstates LTV by 25% at an 80% margin.
• Dividing churn by the ending customer count. The denominator is the count at the start of the period. Using the smaller closing base understates churn and inflates LTV.
• Leaving expansion out of LTV. If net revenue retention is above 100%, the constant-churn lifetime formula understates true lifetime. Either use a cohort-based LTV or state that the figure is conservative.
• Mixing periods. Monthly churn with annual CAC, or annual churn with monthly ARPU, produces a number that is wrong by a factor of twelve.
• Reporting a blended CAC. Paid and organic, self-serve and sales-led have different economics; one blended figure hides which channel is broken.

The LTV:CAC calculator takes ARPU, gross margin, monthly churn and CAC, shows the gross-profit LTV next to the revenue shortcut so the size of the error is visible, and compares the result against the segment table above. If you want the full set of formulas in one place, the SaaS metrics cheat sheet covers all six core metrics.