What data must be on a structured invoice
Fields a Belgian B2B structured invoice needs so software can book it: parties, lines, VAT, totals. EN 16931 and UBL names for vendors; facts you must get right before send.
Updated
A structured invoice is a data file the customer's software can book without retyping. For in-scope Belgian B2B that file is usually UBL XML in the Peppol format (BIS Billing). Standards names matter to vendors. You need the business facts filled in correctly.
Network basics: What is Peppol?. File versus PDF: PDF versus structured invoice.
Three names, one file
| Name | Role |
|---|---|
| EN 16931 | Which facts an e-invoice must be able to carry (parties, lines, VAT, totals) |
| UBL | The XML syntax for those facts |
| Peppol format (BIS Billing) | The profile Access Points expect on Peppol |
- UBL structured invoice
Universal Business Language: the XML encoding of the invoice. In Belgian B2B, "UBL invoice", "XML invoice", and "Peppol invoice" usually mean this file, not a PDF.
A PDF rendered from the same data is a copy. If the XML has 6% VAT and the PDF shows 21%, the XML wins.
Field checklist (Belgian B2B)
| Area | What must be right |
|---|---|
| Seller identity | Legal name, address, enterprise number / VAT as your tool expects |
| Buyer identity | Same for the customer; wrong number is the classic reject |
| Invoice number and issue date | Unique number in your sequence; real issue date |
| Currency | Usually EUR for domestic Belgian B2B |
| Lines | Description, quantity, unit price, line net amount |
| VAT | Rate or regime per line or group; taxable base and VAT amount that match the lines |
| Totals | Net, VAT, and gross that reconcile with lines |
| Payment | IBAN (and structured payment communication when you use one) |
| References (when the buyer needs them) | Order or contract number so their AP can match |
Often useful as well: delivery date, buyer cost centre or reference, and a contact for disputes. Legal wording: Belgian invoice mentions.
Worked example
Atelier Nord SRL invoices Horizon SRL F2026-118 for 10 windows at 21% VAT. The Peppol file (UBL) carries seller 0208:0123456789, the buyer enterprise number, the ten lines, VAT base, VAT amount, and totals that add up. The site PDF is rendered from that XML. If the buyer number is missing in the XML, validation fails even when the PDF looks clean.
Before you hit Send
- Fill every mandatory field your invoicing tool highlights for that customer.
- Double-check the buyer enterprise number (ten digits, including leading zeros).
- Confirm VAT math: line nets + VAT equal the header totals.
- Run validate-before-send if your product offers it (validation errors).
- Archive the structured original, not only the PDF view.
Common mistakes
- Wrong or incomplete buyer number in the XML
- Totals that do not match lines
- VAT treatment that does not match the supply
- Archiving PDF only
- Assuming "delivered on Peppol" means the data was correct
FAQ
What data must be on a structured invoice?
At least parties, unique number, issue date, lines, VAT, totals, and payment details, plus any buyer references they require. That is what EN 16931 and the Peppol format expect.
What is UBL?
The XML syntax of the European e-invoice (EN 16931). On Peppol, UBL is the usual encoding of the BIS Billing invoice.
What is the Peppol format?
For invoices: Peppol BIS Billing, built on EN 16931 in UBL. It is a profile (fields and rules), not a second document beside the XML file.
Do I have to write XML by hand?
No. Invoicing software fills UBL from your screens. Your job is correct parties, lines, VAT, and totals.
Is a PDF the same as a structured invoice?
No. A PDF is a view. The structured file is the source for compliance and booking. Both can come from the same data.
Where does this sit versus the 2026 obligation?
The obligation says you must exchange a structured invoice. This page lists the facts that file must carry. Scope: Belgian e-invoicing obligation.