Finance & Supplier Management

Detecting Over-Invoicing Before Approval with Automated Supplier Invoice Reconciliation

A large property and construction management firm processing hundreds of supplier invoices a month used Docwize to validate every invoice against its procurement system's orders, its supplier master and previously received invoices — blocking over-invoiced, duplicate and unmatched invoices before they reached an approver.

Illustration showing two inventory systems being compared side by side, with a discrepancy highlighted in the reconciliation table

Three-stage validation matrix

Pre-submission, vendor identity and order-and-value checks run on every invoice, with results rendered on the document.

Five order-level reconciliation statuses

Matched, Partially Invoiced, Over Invoiced, Not Invoiced and Invoice With No Order — a live position per purchase order.

Duplicates caught by number and by content

Invoice number and file content hash checked independently so re-sent files are held whatever they are called.

Hundreds of invoices a month, captured from email

Email robot rules, automatic splitting of multi-invoice attachments and AI extraction replace manual capture.

The challenge

The firm ran dozens of active projects, each generating invoices from materials suppliers, subcontractors, plant hire and service providers. Invoice amounts were compared to purchase order lines by hand, supplier credits were reconciled weeks after the original invoice, and by the time a mismatch was found the invoice had usually already been approved. Correcting it meant manual rework and re-processing. Individual invoices often looked correct in isolation; the problem was the cumulative position against each order, which nobody was tracking.

The approach

Docwize captured invoices from the finance mailbox, extracted their content into structured fields, and reconciled them against order data synced from the procurement system. Every check result, the resulting decision and the reason for any block were rendered directly on the invoice document so the approver could see why an invoice was held.

•Catch invoice, credit note and statement emails with an email robot rule, file them to the reconciliation folder and start an invoice-splitting workflow for multi-invoice attachments
•Extract invoice number, type, date, purchase order number, supplier name, VAT and registration numbers, amounts and line items with an AI extraction template
•Sync invoiceable orders from the procurement system — supplier, registration, VAT number, delivered and invoiceable quantities and amounts — into a custom field grid
•Run a validation matrix per invoice: pre-submission checks (valid invoice type, invoice number present, order number present, no duplicate by invoice number or file content hash); vendor identity checks (order link exists, supplier name, VAT and registration match the supplier master); and order-and-value checks (order matches the linked record, invoice total within the order's remaining invoiceable amount)
•Summarise each order as Matched, Partially Invoiced, Over Invoiced, Not Invoiced, or Invoice With No Order, and export approved invoices to the accounting system without re-keying

What the analysis revealed

Over-invoicing was an order-level pattern

Most single invoices were within tolerance. Over-invoicing appeared only when cumulative invoiced value was compared to each order's invoiceable amount — a running total that manual review had never maintained.

Duplicates arrived in more than one form

The same invoice number re-sent, and the same file re-sent under a different name, both occurred. Checking invoice number and file content hash separately caught both.

Identity mismatches were worth flagging

Invoices whose VAT or registration number did not match the supplier master were held for query — a control against mis-keyed supplier records and against fraudulent invoices presented in a known supplier's name.

Outcome

Invoices are now cleared, parked or blocked by rule before an approver sees them, with the block reason and required action written on the document. Proforma invoices are parked as non-payable. The order-level summary gives finance a live position — matched to the cent, partially invoiced, over-invoiced or not yet invoiced — for every open order, and approved invoices flow to the accounting system without manual transfer. Exceptions are handled once, at the gate, rather than reversed after payment.

Finding invoice discrepancies after approval instead of before?

Docwize reconciles every invoice against your orders, supplier master and prior invoices before anyone approves it. Get in touch to discuss your invoice control.

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