# UBL-SR-29

> Bank creditor reference shall occur maximum once

Checked against Peppol BIS Billing 3.0 2026.5

Canonical: https://einvoicecheck.eu/rules/ubl-sr-29

## Official rule text

Bank creditor reference shall occur maximum once

## Why did my invoice fail UBL-SR-29?

The Payment creditor reference (BT-83) carries the remittance/creditor reference — such as an ISO 11649 structured creditor reference — that the buyer must quote when paying. EN 16931 allows at most one such reference per invoice, so this rule forbids supplying it more than once. In UBL it maps to cac:PaymentMeans/cbc:PaymentID, which must not be repeated for this purpose.

## Common causes

- A mapping template emits a second cbc:PaymentID inside cac:PaymentMeans in addition to the creditor reference.
- Multiple cac:PaymentMeans blocks each carry their own creditor reference.
- The creditor reference and an internal payment ID are both written as cbc:PaymentID.

## How do I fix it?

```
Keep a single creditor reference: <cac:PaymentMeans><cbc:PaymentID>RF18000000000539007547034</cbc:PaymentID>...</cac:PaymentMeans> and remove any duplicate cbc:PaymentID elements.
```