Draft reference — content review pending
Customer Retention Rate
The percentage of eligible customers present at the start of a period who remain under the agreed retention definition at the end.
Business question
What share of the eligible starting customer base remained with the business during this period?
Formula
Customer retention rate = ((eligible customers at period start − customers lost from that starting base) ÷ eligible customers at period start) × 100.
Calculation notes
Define the eligible starting base, retention event, period length, and treatment of new customers. New customers should not inflate the starting-base denominator.
Edge-case guidance
If the eligible starting base is zero, report the measure as not available. Account for paused, merged, seasonal, or contract-based customers explicitly.
Required data
| Input | Type | Status | Available source hints |
|---|---|---|---|
| Starting eligible customersCustomers eligible for retention at the start of the period. | Number | Required | CRM · Excel · Google Sheets |
| Lost starting customersStarting-base customers who no longer meet the retention definition. | Number | Required | CRM · Excel · Google Sheets |
Interpretation
Use the measure to understand continuity in the starting customer base and pair it with acquisition, activity, and churn context.
Caution
Retention depends on the customer definition, period length, and activity or contract rule. It should not be treated as the mathematical inverse of churn without matching definitions.
Implementation recommendation
Document the starting cohort and retention event, then segment the result by customer type when the overall rate hides different experiences.
Target guidance
Set the first target from a comparable historical baseline for customer retention rate, then adjust it for strategy, capacity, seasonality, data quality, and relevant market or regulatory context. Review the direction with the accountable business owner rather than treating any external benchmark as universal.