Checking rebar invoices: tonnage, bar diameter and the delivery note

• Different units — the invoice bills kg or tonnes; the site counts bars, bundles or bent shapes from a bar list or cut-and-bend schedule.
• Weight is not exact — the weight on the invoice rarely agrees to the kilo with what the note implies, so the check needs a tolerance, not equality.
• Diameter drives price — D12, D16, D20 and D25 bars may be priced differently; a line billed as the wrong diameter changes the total.
• Fabrication extras — cutting, bending and delivery may be billed as separate lines at their own rates.
• Many deliveries per invoice — fabricated rebar arrives in batches by structural element, and the invoice summarises them.

For example: a supplier invoices 18.4 t of fabricated rebar for a month, across nine deliveries. Someone gathers the nine notes, converts or adds up the weights per diameter, compares them with the invoice lines, looks up the contracted price per tonne for each diameter and decides whether a 0.3 t difference is within what the company accepts. Then the site and the office often do it again, for different reasons.

Diameter and unit slips are two of the common supplier invoice discrepancies; the price side works as described in checking invoices against agreed prices. Concrete has its own pitfalls, covered in ready-mix concrete tickets.

1. 01Delivery notes are photographed on site in the chat group the team already uses; invoices arrive as PDFs or emails.
2. 02Two AI models read each document independently: item, diameter, quantity, unit and price on every line.
3. 03Each line is matched to the rebar contract item by meaning.
4. 04V7 checks rebar tonnage within tolerance; V10 flags a different item, such as D16 vs D22; V9 checks unit consistency; V1 and V8 check the price against the contract.
5. 05What matches is approved automatically; differences go to review with the exact amount. Duplicates are caught by document number plus supplier.

Audiree does not check steel grades, mill certificates or bar schedules against drawings. Audiree is not an ERP, an accounting system or AP payment software. It does not pay suppliers, does not issue delivery notes or invoices, is not a certified tax archive and does not submit anything to the Portuguese tax authority (AT). It does not validate ATCUD codes, QR codes or signatures with the AT — the document number and ATCUD are used to catch duplicates. It gives no tax advice: VAT rates and reverse-charge treatment stay with your accountant. There are no ready-made connectors to specific ERPs; checked data exports to CSV for Excel or for posting in the system you already use.

Audiree is built in Portugal and works today with Portuguese construction companies. Reading does not depend on a document’s layout, so delivery notes and invoices from suppliers in other countries can be read as they are. If you run projects outside Portugal, we run demos with your own documents — but we don’t claim local tax rules or integrations for your market.