# PEPPOL-EN16931-R003

> A Buyer reference (BT-10) or a Purchase order reference (BT-13) must be provided. Add cbc:BuyerReference or cac:OrderReference/cbc:ID.

Checked against Peppol BIS Billing 3.0 2026.5

Canonical: https://einvoicecheck.eu/rules/peppol-en16931-r003

## Official rule text

A buyer reference or purchase order reference MUST be provided.

## Why did my invoice fail PEPPOL-EN16931-R003?

Peppol requires that either a Buyer reference (BT-10) or a Purchase order reference (BT-13) be provided so the receiver can route and match the invoice. At least one of cbc:BuyerReference or cac:OrderReference/cbc:ID must be present.

## Common causes

- Neither cbc:BuyerReference nor cac:OrderReference/cbc:ID is present.
- BuyerReference element included but left empty.
- OrderReference element present but its cbc:ID child is missing or blank.
- The buyer's routing/cost-center reference was not captured during invoice creation.

## How do I fix it?

```
Add a buyer reference: <cbc:BuyerReference>Cost-Center-4711</cbc:BuyerReference>, or an order reference: <cac:OrderReference><cbc:ID>PO-12345</cbc:ID></cac:OrderReference>.
```