Calculate the collection effectiveness index
Enter each month’s starting receivables, billed amount, ending receivables and current receivables. See the collection effectiveness index for each month, with months below your target flagged.
Latest month’s collection effectiveness index
In 2026-10, the collection effectiveness index was 79.0%, below the 85.0% target, and 290,000 of the receivables at the end of the month was past due. Over all months, the index is 83.3%.
Collection effectiveness by month
Each dot is a month’s collection effectiveness index, and red dots fall below target.
Monthly results
| Month | Collected | Collectable | CEI | Past due | Past due share | DSO |
|---|---|---|---|---|---|---|
| 2025-11 | 1,056,000 | 1,200,000 | 88.0% | 144,000 | 15.3% | 28.3 |
| 2025-12 | 999,000 | 1,146,000 | 87.2% | 147,000 | 15.4% | 28.4 |
| 2026-01 | 1,001,000 | 1,159,000 | 86.4% | 158,000 | 16.2% | 28.6 |
| 2026-02 | 1,009,000 | 1,180,000 | 85.5% | 171,000 | 17.2% | 29.0 |
| 2026-03 | 1,019,000 | 1,203,000 | 84.7% | 184,000 | 18.1% | 29.3 |
| 2026-04 | 1,030,000 | 1,227,000 | 83.9% | 197,000 | 19.0% | 29.6 |
| 2026-05 | 1,039,000 | 1,250,000 | 83.1% | 211,000 | 19.9% | 30.0 |
| 2026-06 | 1,049,000 | 1,275,000 | 82.3% | 226,000 | 20.8% | 30.3 |
| 2026-07 | 1,060,000 | 1,301,000 | 81.5% | 241,000 | 21.8% | 30.7 |
| 2026-08 | 1,069,000 | 1,326,000 | 80.6% | 257,000 | 22.7% | 31.0 |
| 2026-09 | 1,080,000 | 1,353,000 | 79.8% | 273,000 | 23.6% | 31.4 |
| 2026-10 | 1,090,000 | 1,380,000 | 79.0% | 290,000 | 24.5% | 31.8 |
| Total | 12,501,000 | 15,000,000 | 83.3% | – | – | – |
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Calculation method
Collected = Starting receivables + Billed − Ending receivables Collectable = Starting receivables + Billed − Current receivables CEI = Collected ÷ Collectable All-month index = Σ Collected ÷ Σ Collectable Past due = Ending receivables − Current receivables Past due share = Past due ÷ Ending receivables DSO = Ending receivables ÷ Billed × 30
The index compares collected in the month with what could have been collected, calculated as receivables at the start plus billed less current receivables at the end, so 100% means every amount due was collected. Days sales outstanding counts each month as 30 days, and receivables should exclude amounts written off before entry.
Collection effectiveness index
The collection effectiveness index compares the amount collected in a month with the amount that could have been collected. It uses receivables at the start, amounts billed, receivables at the end and the current part of ending receivables.
The result shows the collection effectiveness index alongside past due receivables and days sales outstanding. These figures show collection performance from different views.
Common questions
What is the collection effectiveness index?
The collection effectiveness index compares what was collected with what could have been collected in a month. It uses receivables at the start, billed amounts, receivables at the end and current receivables.
What is the collection effectiveness index formula?
Collected is receivables at the start plus billed less receivables at the end. Collectable is receivables at the start plus billed less current receivables at the end, and the index is collected divided by collectable.
How do I calculate CEI?
Divide collected by collectable for each month. This calculator also works out the index across all entered months from total collected divided by total collectable.
How does the collection effectiveness index compare with days sales outstanding?
The collection effectiveness index measures collected amounts against what could have been collected. Days sales outstanding divides ending receivables by billed amounts and counts each month as 30 days.
How does collection effectiveness differ from collection efficiency?
The collection effectiveness index uses receivables at the start and end of the month, billed amounts and current receivables. Collection efficiency measures instalments collected against instalments billed.