SaaS churn rate measures the share of customers or recurring revenue lost from an existing customer base over a defined period. Customer churn counts customers that leave. Revenue churn measures the recurring revenue lost through cancellations and contraction.
SaaS Churn Rate Formula
| Metric | Formula | What it measures |
|---|---|---|
| Customer churn rate | Customers from the starting cohort lost during the period ÷ customers at the start × 100 | The share of the starting customer base that left. |
| Gross revenue churn rate | (Churned recurring revenue + contraction revenue) ÷ beginning recurring revenue × 100 | The share of starting recurring revenue lost before expansion is added. |
The denominator has to match the measurement. MRR losses should be compared with beginning MRR. ARR losses should be compared with beginning ARR. New customers acquired during the period do not belong in the starting cohort.
Customer churn gives every lost account the same weight. Revenue churn weights the loss by recurring revenue, so customer size changes the result.
Best suited to the question: how much of the starting customer base left?
Best suited to the question: how much recurring revenue disappeared from the starting base?
What Belongs in the Churn Calculation?
| Item | Treatment | Reason |
|---|---|---|
| Customer cancellation | Customer churn | The customer leaves the starting cohort. |
| Recurring revenue lost when a customer cancels | Gross revenue churn | The recurring revenue disappears from the existing base. |
| Downgrade or contraction | Gross revenue churn | The customer remains, but recurring revenue falls. |
| New customer revenue | Exclude | It belongs to acquisition and growth rather than loss from the starting cohort. |
| Expansion from retained customers | Exclude from gross churn | Expansion belongs in net retention calculations rather than gross churn. |
Monthly Churn and Annual Churn Are Not the Same Rate
A monthly churn percentage cannot be converted to an annual rate by multiplying it by 12. Repeated monthly losses compound against a shrinking starting cohort.
Annualized churn = 1 – (1 – monthly churn)12
At a constant 5% monthly customer churn rate, the annualized loss of the original customer base is about 46%, not 60%.
ChartMogul notes that 5% monthly customer churn corresponds to an annual loss of nearly 46% of the existing customer base. Its SaaS data also show a strong ARPA relationship: businesses below $10 ARPA can see customer churn around 6% to 7% per month, while businesses at $500 ARPA or more are closer to 1% to 2% per month. These figures describe ChartMogul’s observed SaaS population, not a universal quality threshold. ChartMogul customer churn methodology
Same Customer Churn, Different Revenue Impact
Assume a SaaS company begins the month with 100 customers and $100,000 of MRR. Five customers leave during the month.
| Scenario | Customers lost | MRR lost | Customer churn | Revenue churn |
|---|---|---|---|---|
| Five small customers leave | 5 | $2,500 | 5.0% | 2.5% |
| One large customer and four small customers leave | 5 | $15,000 | 5.0% | 15.0% |
Both scenarios lose 5% of the customer base. The second loses six times as much MRR. Customer churn alone therefore cannot show whether the lost accounts were economically small or material to the recurring revenue base.
Gross Churn vs Net Retention
Gross revenue churn measures revenue loss before expansion. Net revenue retention includes expansion from customers that remain in the starting cohort. The two measures answer different questions about the same customer base.
NRR remains above 100% because retained customers expand spending.
Other customers may still be cancelling or reducing recurring spend.
Separate gross churn or GRR from expansion before treating strong NRR as evidence that the entire customer base is stable.
What Is a Good SaaS Churn Rate?
There is no single churn threshold that applies across SaaS. Customer size, pricing, contract length, product category, company stage, and measurement period can materially change the expected rate.
A useful benchmark therefore needs a comparable customer and contract profile. Monthly SMB logo churn should not be compared directly with annual enterprise revenue churn, and a customer-count benchmark should not be applied to a revenue-based metric.
A company may disclose logo churn, gross revenue churn, GRR, NRR, renewal rates, or only qualitative retention commentary. Before comparing two businesses, verify the metric type, customer cohort, revenue base, reporting period, and treatment of contraction and expansion.
How Churn Changes the Investor Reading
| Investor question | What churn can reveal | What still needs another metric |
|---|---|---|
| How much replacement growth is required? | Higher churn means more new revenue must be added before total recurring revenue can grow. | Acquisition cost and sales efficiency determine how expensive that replacement is. |
| Are large accounts driving the risk? | Revenue churn can expose losses that customer churn understates when account sizes differ. | Customer concentration and segment disclosures are still needed. |
| Is reported growth coming from the existing base? | Gross churn shows how much revenue is leaking before expansion and new customers compensate for it. | GRR and NRR separate retention from account expansion. |
| Does lower churn justify a higher valuation? | Lower recurring-revenue loss can improve revenue durability. | Growth, margins, cash flow, acquisition economics, competitive position, and valuation expectations still matter. |
Related SaaS Metrics
Use CAC to see how expensive it is to acquire the customers needed to replace churned accounts and support further growth.
Use the Magic Number to examine how efficiently sales and marketing spending is producing new recurring revenue.
Use valuation multiples to place retention quality beside growth, margins, cash flow, and the price investors are paying for the business.