LTV / CAC : La formule-clé de la rentabilité client

LTV / CAC: The Key Formula for Customer Profitability

As recurring revenue models become more prevalent, the ability to sustainably acquire profitable customers becomes a central issue. The LTV / CAC ( Lifetime Value / Customer Acquisition Cost ) ratio allows for the measurement of this efficiency and is one of the most closely monitored indicators by investors, especially in sectors such as SaaS, e-commerce, fintech, and edtech.

What Does the LTV / CAC Ratio Measure?

LTV (Lifetime Value) : The average revenue generated by a customer over their active lifetime. It reflects the total economic value of a customer . CAC (Customer Acquisition Cost) : The average cost to acquire a customer, including marketing, advertising, and sales expenses related to acquisition.

Standard Formula:

LTV / CAC = Customer Lifetime Value / Customer Acquisition Cost

This ratio indicates how many euros of value are generated for each euro invested in acquisition.

It Evaluates the Profitability of Growth

A LTV / CAC ratio > 3 generally means that the company generates enough customer value to cover acquisition costs and produce a usable surplus. Below 1, growth mechanically destroys value.

Indicator of Sustainable Product-Market Fit

A good ratio signals that the product meets a real need, that customers stay, pay, and are potentially loyal or monetizable in the long term.

The ratio helps determine if the company can invest more in acquisition without compromising its financial balance and when to accelerate marketing spending.

A high CAC can be tolerated if the LTV is significantly higher, but a growing CAC with a stable LTV is a signal of saturation or declining efficiency.

Interpretation: What Do the Thresholds Indicate?

LTV / CAC Ratio Interpretation

< 1 Value-Destructive Growth

1 – 2 Fragile Equilibrium, Low Margin of Maneuver

3 – 5 Expected Standard in Healthy Growth Phase

5

High Economic Efficiency, Scalability Capability

Note: A very high ratio (>7) may also indicate underinvestment in sales .

LTV is often overestimated if it is based on unvalidated projections (e.g., unstable churn). Underestimated CAC

Not including indirect costs (sales salaries, tools, events, content) distorts the ratio. Inter-Model Comparison

An acceptable ratio in B2C (e.g., 2.5) is not necessarily suitable in B2B, where order values are higher. Gross vs. Net LTV

Ideally, LTV should be net of service costs to reflect the real profitability of a customer.

– Enhance customer satisfaction and retention

– Develop a loyalty program or community Reduce CAC

– Optimize acquisition channels (SEO, referrals, partnerships)

– Build brand to reduce marginal acquisition cost

Tomorrow we will address the Net Revenue Retention, the indicator of customer love .

D’après FrenchWeb.