# UBL-CR-028

Quoted from a public specification. This page is not a validator, and it is not tax, legal, or accounting advice.

- Country: EU
- Syntax: UBL
- Severity: warning
- Statement language: en
- Last verified: 2026-10-18

## Official statement

> A UBL invoice should not include the BillingReference Xpath

Source: https://docs.peppol.eu/poacc/billing/3.0/rules/ubl-tc434/UBL-CR-028/

Peppol BIS Billing 3.0, May 2026 release, EN 16931 model bound to UBL

Severity note: warning, from the Flag column of the Peppol BIS Billing 3.0 UBL rules index retrieved 2026-10-18.

## Plain-language reading

A UBL invoice should not include the BillingReference Xpath. The statement says "should not include the BillingReference Xpath", not "shall", and it has no period. The two names are separated by a space. The statement spells Xpath. The statement does not name InvoiceDocumentReference. The flag is warning. The context is the same string as BR-CO-18. The published test is not(cac:BillingReference/cac:InvoiceDocumentReference/cbc:XPath). The test spells XPath. The path uses a slash. It does not call exists.

## What to change

Leave BillingReference Xpath out of the UBL invoice.

## Illustration

Illustration of the condition in the official statement. Not an example published by the source.

**Fails the stated condition.** The invoice includes BillingReference Xpath.

**Passes the stated condition.** The invoice does not include BillingReference Xpath.

## Published context and test

Copied from the source. Not reimplemented on this page.

```
/ubl:Invoice | /cn:CreditNote
```

```
not(cac:BillingReference/cac:InvoiceDocumentReference/cbc:XPath)
```

[All rule notes](https://einvoicegoblin.com/rules/index.md) · [JSON](https://einvoicegoblin.com/rules/UBL-CR-028.json) · [HTML](https://einvoicegoblin.com/rules/UBL-CR-028/) · [llms.txt](https://einvoicegoblin.com/llms.txt) · [Invoice page](https://einvoicegoblin.com/) · [Privacy](https://einvoicegoblin.com/privacy.html)