# BR-O-13 Not-subject-to-VAT invoice must have no non-O document allowance

An invoice that contains a VAT breakdown (BG-23) with VAT category code (BT-118) "Not subject to VAT" (O) shall not contain a document level allowance (BG-20) whose Document level allowance VAT category code (BT-95) is not "Not subject to VAT".

## Problem Description

> **ERROR**: EN 16931 VAT category rule

## Context and Significance

An invoice with a category O breakdown is entirely outside the scope of VAT, so all document level allowances must also use category O. In practice, the error occurs when a global discount keeps the category of an earlier taxable template, such as Z or S.

## Solution

Give every document level allowance category O (BT-95 = O), or remove the non-O allowances.

- [Validate XML](/en/xrechnung-validator?source=resource&rule=BR-O-13)
- [Convert invoice](/en/pdf-to-xrechnung?source=resource&rule=BR-O-13)

## Valid Examples

- O breakdown present and every document allowance has BT-95 = O

## Invalid Examples

- O breakdown present but a document allowance has BT-95 = Z

## Code Examples

### Valid XML
```
<cac:AllowanceCharge>
  <cbc:ChargeIndicator>false</cbc:ChargeIndicator>
  <cbc:Amount currencyID="EUR">10.00</cbc:Amount>
  <cac:TaxCategory><cbc:ID>O</cbc:ID><cac:TaxScheme><cbc:ID>VAT</cbc:ID></cac:TaxScheme></cac:TaxCategory>
</cac:AllowanceCharge>
```

### Invalid XML
```
<cac:AllowanceCharge>
  <cbc:ChargeIndicator>false</cbc:ChargeIndicator>
  <cbc:Amount currencyID="EUR">10.00</cbc:Amount>
  <cac:TaxCategory>
    <cbc:ID>Z</cbc:ID>
    <cbc:Percent>0</cbc:Percent>
    <cac:TaxScheme><cbc:ID>VAT</cbc:ID></cac:TaxScheme>
  </cac:TaxCategory>
</cac:AllowanceCharge>
```

## Affected Fields

- [BT-118 VAT category code](/resources/xrechnung/bt-118-vat-category-code)
- [BT-95 Document level allowance VAT category code](/resources/xrechnung/bt-95-document-level-allowance-vat-category-code)

## Related Rules

- [BR-O-01](/resources/kosit-validator-errors/br-o-01-not-subject-vat-breakdown-required)
- [BR-O-11](/resources/kosit-validator-errors/br-o-11-forbids-other-vat-breakdowns)
- [BR-O-14](/resources/kosit-validator-errors/br-o-14-forbids-non-o-charges)

## Validation Tools

- [Official KoSIT Validator](https://github.com/itplr-kosit/validator): Run the official KoSIT validator with the XRechnung configuration to check EN 16931 and XRechnung rules.
- [Convert PDF to XRechnung](/pdf-to-xrechnung): Find validation errors during conversion and review each correction.

## Related Resources

- [Official Specification](https://docs.peppol.eu/poacc/billing/3.0/rules/ubl-tc434/)
- [Test Suite](https://github.com/itplr-kosit/xrechnung-testsuite)
- [All validation errors](/resources/kosit-validator-errors): Overview of the EN 16931, XRechnung and Peppol validation rules explained here.