What Is Churn Rate?

Customer churn rate = (Customers lost during period ÷ Customers at start of period) × 100. Revenue churn rate = (MRR lost during period ÷ MRR at start of period) × 100. Net revenue churn accounts for both losses and expansions — net negative churn (when expansion revenue exceeds churned revenue) is the holy grail of SaaS economics. Monthly churn of 2% annualizes to roughly 22% annual churn — meaning a company loses nearly a quarter of its customer base each year and must replace it just to stay flat. Reducing monthly churn from 3% to 2% increases a customer's expected lifetime by 50%. Churn is caused by product-market fit gaps, pricing misalignment, poor customer success, competitive switching, and involuntary churn (failed payments). Leading indicators of churn include product usage decline, support ticket volume, and Net Promoter Score trends.

Churn is the biggest lever on long-term subscription business value — more impactful than CAC in most mature businesses. A 1–2% improvement in monthly churn can double customer lifetime value. A marketing consultant or business advisor can help you identify churn drivers, design retention interventions, and model the long-term revenue impact of churn reduction programs.