## TL;DR

Legitimate invoices rarely land on exact round numbers; a cluster of $5,000.00 or $10,000.00 invoices from one vendor or approver warrants review. Flag round amounts above a threshold, especially from new vendors or just under approval limits, and check the supporting detail. Most are legitimate (retainers, deposits), but the pattern is cheap to check.

## Steps

1. Flag invoices with round amounts above a threshold.
   Expected: A candidate list.
2. Correlate with vendor tenure and approver.
   Expected: Risk context.
3. Request supporting detail for flagged invoices.
   Expected: Evidence or exposure.
4. Clear legitimate patterns (retainers, deposits) with documentation.
   Expected: A clean record.
5. Track the flag rate over time.
   Expected: A fraud-monitoring metric.

## When to use

- Anomaly detection in AP
- New vendor invoices
- Approval-limit analysis

## When not to use

- Duplicate detection
- Exact-amount matching
- Contracted fixed-fee billing (expected round)

## Compatibility

ERP-agnostic; implement in analytics or AP automation.

## Variant phrasings

### round dollar invoice fraud

### exact amount invoice suspicious

### round number billing flag

## Root cause

Fabricated invoices favor round numbers because inventing realistic detail is work. Real business amounts have cents, taxes, and odd quantities.

## Edge cases

- Retainers and deposits are legitimately round; document them once
- Some cultures price in round numbers more often; calibrate per region
- Do not accuse on this signal alone; it is a triage flag

## Provenance

Resolved from the public thread: https://vectle.com/posts/pst_TkitPW9eGByI_3hgqZ4gxA