Customer Lifetime Value (LTV)

What Is Customer Lifetime Value (LTV)?

Customer Lifetime Value (LTV), also written as CLV or CLTV, is the total gross profit a business expects to earn from a single customer over the entire duration of their relationship. It answers a fundamental question every founder must be able to answer: how much is one customer worth to your business?

LTV is most powerful when compared directly to CAC (Customer Acquisition Cost). The LTV:CAC ratio is one of the most important metrics investors use to evaluate startup health because it reveals whether the business is building or destroying value with every customer it acquires.

How to Calculate LTV

The most straightforward LTV formula for a subscription business:

LTV = (ARPU × Gross Margin %) ÷ Monthly Churn Rate

Where:

• ARPU = Average Revenue Per User per month
• Gross Margin % = percentage of revenue remaining after cost of goods sold
• Monthly Churn Rate = percentage of customers lost each month

Example: ARPU = $50/month, Gross Margin = 70%, Monthly Churn = 5% LTV = ($50 × 0.70) ÷ 0.05 = $35 ÷ 0.05 = $700

For transactional or non-subscription businesses, LTV is calculated from cohort data: track how much a group of customers acquired in the same period actually spend over 12, 24, and 36 months.

Why Gross Margin Matters in LTV

LTV must be calculated on gross profit, not revenue. If a customer pays $50/month but it costs $20/month in hosting, support, and delivery to serve them, your gross profit is $30/month — and your LTV should reflect $30, not $50.

Using revenue instead of gross profit inflates LTV by the inverse of your gross margin. A business with 60% gross margin that calculates LTV on revenue is overstating its LTV by 67%.

The Relationship Between LTV and Churn

Churn is the dominant variable in LTV. Small changes in churn rate have outsized effects:

• At 2% monthly churn: average customer lifetime = 50 months
• At 5% monthly churn: average customer lifetime = 20 months
• At 10% monthly churn: average customer lifetime = 10 months

This means reducing monthly churn from 5% to 2% more than doubles LTV — without changing pricing, ARPU, or gross margin. In most startups, improving retention is the single highest-ROI lever for improving unit economics.

LTV Expansion: Net Revenue Retention

LTV can grow beyond the initial contract value if customers expand their usage over time — buying more seats, upgrading plans, or purchasing add-ons. This is measured by Net Revenue Retention (NRR), which tracks revenue from a cohort of customers over time including expansions and contractions.

An NRR above 100% means your existing customer base is growing in value even without adding new customers. World-class SaaS businesses (Snowflake, Datadog) have historically achieved NRR of 130–150%, meaning their LTV curve compounds upward over time.

In SEA B2B SaaS, NRR of 100–110% is a realistic benchmark for early-stage companies with product-market fit.

LTV Benchmarks and Investor Expectations

The standard investor benchmark is LTV:CAC ≥ 3:1. Below 1:1 indicates the business destroys value with every acquisition. Above 5:1 may suggest underinvestment in growth (you could afford to spend more on acquisition and grow faster).

CAC payback period — how long until LTV exceeds CAC — is equally important. Investors generally want to see payback periods under 12 months for B2B SaaS and under 6 months for B2C.

Improving LTV

The primary levers for improving LTV:

Reduce churn: Improve onboarding, increase product stickiness, build switching costs, invest in customer success.

Increase ARPU: Add premium tiers, upsell features, introduce usage-based pricing components that grow with customer usage.

Improve gross margin: Reduce cost of service delivery through automation, infrastructure optimisation, and process efficiency.

Expand within accounts: Cross-sell additional products, grow seat counts, introduce enterprise-tier contracts.