# BR-50 Credit transfer requires a payment account identifier

A Payment account identifier (BT-84) shall be present if Credit transfer (BG-17) information is provided in the Invoice.

## Problem Description

A Payment account identifier (BT-84) shall be present if Credit transfer (BG-17) information is provided in the Invoice.

> **ERROR**: XRechnung 3.0

## Context and Significance

This rule comes from the EN16931 core semantic model enforced by the KoSIT XRechnung 3.0.2 Schematron, ensuring invoices carry the mandatory data needed for automated processing.

## Solution

Provide cac:PayeeFinancialAccount/cbc:ID, usually the IBAN, for every credit transfer payment means group.

- validate
- convert

## Valid Examples

- BT-84 = DE89370400440532013000 with credit transfer

## Invalid Examples

- Credit transfer means with no PayeeFinancialAccount ID

## Code Examples

### Valid XML
```
<cac:PaymentMeans>
  <cbc:PaymentMeansCode>58</cbc:PaymentMeansCode>
  <cac:PayeeFinancialAccount>
    <cbc:ID>DE89370400440532013000</cbc:ID>
  </cac:PayeeFinancialAccount>
</cac:PaymentMeans>
```

### Invalid XML
```
<cac:PaymentMeans>
  <cbc:PaymentMeansCode>58</cbc:PaymentMeansCode>
  <cac:PayeeFinancialAccount/>
</cac:PaymentMeans>
```

## Affected Fields

- [BT-84 Payment account identifier](/resources/xrechnung/bt-84-payment-account-identifier)

## Related Rules

- [BR-49](/resources/kosit-validator-errors/br-49-payment-means-type-code-required)
- [BR-61](/resources/kosit-validator-errors/br-61-credit-transfer-account-required)

## Validation Tools

- [Official KoSIT Validator](https://erechnungsvalidator.service-bw.de/): Validate your XRechnung files against all BR-DE rules.
- [Convert PDF to XRechnung](/pdf-to-xrechnung): Automatic validation error fixes when converting.

## Related Resources

- [Official Specification](https://xeinkauf.de/xrechnung/)
- [Test Suite](https://github.com/itplr-kosit/xrechnung-testsuite)
- [Complete Error List](/resources/kosit-validator-errors): Overview of all German XRechnung validation rules.