Three-way matching is only useful when exceptions are explainable.
Comparing an invoice with its purchase order and goods receipt can reveal discrepancies before an accounts-payable reviewer acts. The difficult part is not just flagging a row: it is showing the exact rule, source evidence, ambiguity and next review step without pretending a flag proves fraud or loss.
Run the free CSV exception review →No account required. The prototype processes the supplied files in your browser. Start with synthetic records; do not upload confidential data without an approved handling process.
What a three-way match should compare
1. Invoice
Supplier identity, invoice identifier, purchase-order reference, SKU or line identifier, quantity, unit price and line total.
2. Purchase order
The approved supplier, ordered quantity, agreed unit price and unique order-line identity. Duplicate keys can make a match ambiguous.
3. Goods receipt
Recorded accepted quantities against the order line. Missing receipt data may mean a control gap—or that the workflow does not require that record.
4. Review evidence
Each exception should preserve the rule, row references, observed values, input scope and reviewer decision. A number without traceable context is not an audit trail.
Exception types worth separating
- Identity issues: missing purchase-order line, supplier mismatch, blank key or duplicate invoice ID.
- Commercial differences: invoice price differs from the order, quantity exceeds the order, or line total does not equal quantity multiplied by unit price.
- Receipt differences: invoiced quantity exceeds recorded receipt quantity, or the receipt row is absent.
- Ambiguity: more than one order line matches the same key. A safe system should report the ambiguity instead of silently selecting a row.
A useful review process
- Agree the source files, column mapping, currency and matching keys.
- Run deterministic checks and preserve the exact input versions used.
- Review each exception against original records and the applicable commercial terms.
- Record whether the finding was confirmed, explained, corrected or dismissed.
- Compare the tool's output with the team's existing method, including false positives and missed cases.
Try it with sample data
LedgerProof includes a synthetic demonstration and downloadable source CSVs. The current prototype checks duplicate invoice IDs, missing PO lines, supplier mismatches, duplicate matching PO lines, unit-price differences, quantity overages, missing receipt records and line-total arithmetic.
- Synthetic invoice lines
- Synthetic purchase-order lines
- Synthetic goods receipts
- Open the review engine
Where the prototype stops
It is a browser-side CSV review tool, not a full accounts-payable platform. It has no accounting integrations, OCR/PDF extraction, approval workflow, payment controls, scheduled monitoring, multi-user workspace or audit-grade access control. The current version does not prove that it is better than an existing customer's controls; that must be measured against a labelled test set and current workflow.
For implementation and finance-operations teams
The useful evaluation question is narrow: does this review catch a meaningful discrepancy your current process misses, reduce investigation time, or improve the evidence your team can hand over? Compare it with your existing method before deciding whether it belongs in your workflow.
Test a synthetic workflow →