Accounting Retention Rate (Per-Unit) Calculator
Calculate the percentage of starting customer, account, or subscription units retained during an accounting period.
Overview
Use this Accounting Retention Rate (Per-Unit) Calculator to estimate how many customers, accounts, subscriptions, or other units from the start of a period remained at the end. Enter beginning units, total ending units, and units added during the period to separate retention from growth through new acquisition.
How it works
Per-unit retention removes new additions from the ending unit count, then compares the remaining units with the number at the beginning of the period. The calculation is: retained units = ending units minus new units; retention rate = retained units divided by beginning units, expressed as a percentage. Churn is the portion of beginning units that was not retained. This approach measures unit retention rather than revenue retention, so it does not account for changes in pricing, spend, or unit value.
How to use this calculator
- 1Enter the number of active units at the start of the accounting period.
- 2Enter the total active units at the end of the same period.
- 3Add the number of new units acquired or activated during the period.
- 4Review the retention rate, retained units, lost units, and churn rate.
- 5Use consistent unit definitions and period dates when comparing results over time.
Example Calculation
Units at Start of Period
1000
Units at End of Period
950
New Units Added During Period
100
Per-Unit Retention Rate
85.0%
After removing 100 new customers from the 950 ending customers, 850 customers from the starting group remain. The per-unit retention rate is 85.0%, and 150 starting customers were lost.
Frequently asked questions
What is per-unit retention rate?
Per-unit retention rate is the percentage of units present at the start of a period that are still present at the end, after excluding new units added during the period.
What is the formula for accounting retention rate per unit?
The formula is: (ending units minus new units) divided by beginning units, multiplied by 100.
Why are new units removed from ending units?
New units represent growth through acquisition or activation, not retention of the starting group. Removing them helps isolate the retention result.
What counts as a unit for this calculation?
A unit can be a customer, account, subscriber, contract, member, product license, or another consistently tracked item.
Can the retention rate be over 100%?
It can be over 100% if the ending units minus reported new units exceeds beginning units. This may reflect reactivations, classification changes, acquisitions, or incomplete new-unit data and should be reviewed.
What is the difference between unit retention and revenue retention?
Unit retention counts retained customers or other units. Revenue retention measures retained revenue and can be affected by upgrades, downgrades, price changes, and customer spending.
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Assumptions and warnings
Assumptions
- All three figures refer to the same accounting period and use the same definition of a unit.
- New units are excluded from the ending total to isolate retention of the starting group.
- A unit is counted once at the start and once at the end; changes in unit value or revenue are not included.
- Results are operational estimates and may differ from retention figures used in formal financial reporting.
Warnings
- This calculator provides an estimate only and is not accounting, financial, or professional advice.
- Check that acquisitions, reactivations, mergers, and unit-definition changes are treated consistently before using the result for reporting or decisions.