Key takeaways
- The Peppol network carries more than invoices: it also moves the order, the catalogue and the despatch advice.
- Each document maps to a Peppol BIS profile and builds on the same UBL 2.1 syntax as the invoice.
- These documents connect along the purchase-to-pay cycle, from catalogue to invoice, with no re-keying.
- In Belgium, only the invoice falls under the B2B mandate; the order and the catalogue stay optional.
Peppol carries more than invoices
Most businesses meet Peppol through the invoice, because that is what the B2B mandate targets. But Peppol documents do not stop at billing. The same network moves the documents that come before it in the trading relationship: the product catalogue, the order, the order response, the despatch advice. In other words, Peppol covers a good part of the purchase-to-pay cycle.
These documents are defined by OpenPeppol, the association that governs the network, as Peppol BIS profiles, exactly like the billing profile. They share the UBL 2.1 syntax and follow the same technical path. Understanding this set of documents means seeing Peppol for what it is: an infrastructure for exchanging business documents, not a mere invoice channel.
This article walks through the network's main procurement documents. For the network itself, read Understanding the Peppol network in 5 minutes; for the invoice, Peppol BIS Billing 3.0: what the format contains.
The electronic order: Order and Order Response
The first structured procurement document is the order. On Peppol, it belongs to the Peppol BIS Ordering profile, which defines two UBL 2.1 documents: the order (Order), issued by the buyer, and the order response (Order Response), returned by the seller. Through that response, the seller can accept the order, accept it with amendments where the contract allows, or reject it.
This symmetry carries a clear legal consequence. According to the OpenPeppol specification, an accepted order "has the commercial and legal status of a contract". The electronic order is therefore not a structured email: it is the act that binds both parties, traceable and machine-readable end to end.
- 1
Catalogue
UpstreamThe supplier publishes its items and prices to the buyer (Peppol BIS Catalogue).
- 2
Order
Step 1The buyer issues an order from the agreed items (Order).
- 3
Order response
Step 2The seller accepts, amends or rejects (Order Response).
- 4
Despatch advice
Step 3The seller announces the goods dispatched and the quantities (Despatch Advice).
- 5
Invoice
Step 4The seller bills the delivery under Peppol BIS Billing 3.0.
The electronic catalogue: presenting your products on Peppol
Upstream of the order sits the catalogue. The Peppol BIS Catalogue profile lets a supplier send a buyer, in structured form, the list of its items with their prices and characteristics. It too builds on UBL 2.1 and comprises two documents: the catalogue (Catalogue) and its response (Catalogue Response), by which the buyer accepts or rejects the content received.
The benefit is tangible for repeat purchasing. Instead of re-keying references and prices, the buyer loads the catalogue straight into its system, where it becomes the basis for later orders. The specification puts it plainly: the catalogue "contains the articles that the buyer and seller have agreed on in a contract". It is not a marketing showcase but a shared, maintained purchasing reference.
The despatch advice and the network's other documents
Between the order and the invoice sits the despatch advice. The Peppol BIS Despatch Advice profile covers a UBL 2.1 document by which the supplier informs the buyer of the goods dispatched: delivery period, quantities sent, and details for cross-checking against the order and for goods receipt. It smooths the receiving process and prepares the match against the invoice.
The network provides further documents for more specific needs: the invoice response (Invoice Response), which lets the buyer signal the status of an invoice received, or the message level response (Message Level Response), which acknowledges a document at the technical level. All follow the same profile logic and the same UBL 2.1 syntax.
common syntax
order, catalogue, advice and invoice
corners
the same exchange model as the invoice
re-keying targeted
from catalogue to invoice
One connection for the whole chain
The common thread across these documents is decisive: they use the same four-corner network and the same access points as the invoice. A business connected to Peppol for billing uses the same infrastructure to send or receive an order, a catalogue or a despatch advice. There is no second network to join and no new address to obtain: the company's Peppol identifier serves every document.
What varies is your software's features. Sending a Peppol invoice does not mean being able to handle an order or a catalogue: each document requires the tool to produce, validate and interpret it. That is a point to check if your activity rests on recurring purchasing or on public procurement, where the electronic order and catalogue are more widespread.
| Invoice (Billing) | Order / Catalogue | |
|---|---|---|
| Travels over the Peppol network | ||
| Builds on the UBL 2.1 syntax | ||
| Covered by the Belgian B2B mandate (1 January 2026) | ||
| Adopted by agreement between partners |
Invoice over Peppol, without touching the UBL
YouInv generates, validates and sends your Peppol BIS Billing 3.0 invoices over the network, in a few clicks.
What is mandatory in Belgium, and what is not
The network and the mandate must be told apart clearly. The Belgian business-to-business e-invoicing mandate, set for 1 January 2026, applies to the structured invoice, not to the other Peppol documents. The order, the catalogue and the despatch advice remain network capabilities that partners adopt when it is useful to them, without being required to by law.
That distinction avoids two mistakes. The first would be to think you must set up the electronic order and catalogue to comply: you do not, the invoice satisfies the mandate. The second would be to ignore these documents even though they exist: for a business handling purchasing at volume, they naturally extend the automation already gained on the invoice. For the exact timeline and scope of the mandate, see Peppol Belgium: the B2B mandate from 1 January 2026.
Further reading
- Understanding the Peppol network in 5 minutes: the four-corner model and access points.
- Peppol BIS Billing 3.0: what the format contains: the profile of the invoice and the credit note.
- The UBL 2.1 format explained: the syntax common to all these documents.
The reference sources prevail: the Peppol BIS specifications published by OpenPeppol for the post-award documents.
Which documents travel over the Peppol network besides the invoice?
The Peppol network carries several structured procurement documents in addition to the invoice: the order and its response (Peppol BIS Ordering profile), the catalogue and its response (Peppol BIS Catalogue) and the despatch advice (Peppol BIS Despatch Advice). All are built on the UBL 2.1 syntax, like the invoice.
Are the Peppol order and catalogue mandatory in Belgium?
No. The Belgian B2B e-invoicing mandate, set for 1 January 2026, applies to the structured invoice. The other Peppol documents such as the order, the catalogue or the despatch advice remain optional network capabilities, adopted according to what trading partners need.
What is the Peppol BIS Ordering profile?
Peppol BIS Ordering is the profile that covers the electronic order. It defines two UBL 2.1 documents: the order (Order), sent by the buyer, and the order response (Order Response), by which the seller accepts, accepts with amendments or rejects. An accepted order has the status of a contract.
What is the electronic catalogue used for on Peppol?
The electronic catalogue (Peppol BIS Catalogue profile) lets a supplier send a buyer, in structured form, the list of its items with their prices. The buyer can then load it into its purchasing system and respond with acceptance or rejection through the Catalogue Response document.
Do you need different software for the Peppol order and the invoice?
No. Peppol procurement documents use the same four-corner network and the same access points as the invoice. One tool connected to Peppol can, depending on its features, produce and receive the invoice as well as the order or the catalogue, with no second connection.
