# BR-S-09 Standard-rated VAT amount must equal taxable amount times rate

The VAT category tax amount (BT-117) in a VAT breakdown (BG-23) where the VAT category code (BT-118) is "Standard rated" shall equal the VAT category taxable amount (BT-116) multiplied by the VAT category rate (BT-119).

## Problem Description

The VAT category tax amount (BT-117) in a VAT breakdown (BG-23) where the VAT category code (BT-118) is "Standard rated" shall equal the VAT category taxable amount (BT-116) multiplied by the VAT category rate (BT-119).

> **ERROR**: XRechnung 3.0

## Context and Significance

This EN16931 rule enforces the arithmetic of the standard-rated (category S) VAT breakdown so the declared tax matches the taxable base and rate.

## Solution

Recompute BT-117 as BT-116 × BT-119 / 100 and write the rounded result into the standard-rated TaxSubtotal TaxAmount.

- validate
- convert

## Valid Examples

- BT-116 = 100.00, BT-119 = 19, BT-117 = 19.00

## Invalid Examples

- BT-116 = 100.00, BT-119 = 19, but BT-117 = 20.00

## Code Examples

### Valid XML
```
<cac:TaxSubtotal>
  <cbc:TaxableAmount currencyID="EUR">100.00</cbc:TaxableAmount>
  <cbc:TaxAmount currencyID="EUR">19.00</cbc:TaxAmount>
  <cac:TaxCategory><cbc:ID>S</cbc:ID><cbc:Percent>19</cbc:Percent></cac:TaxCategory>
</cac:TaxSubtotal>
```

### Invalid XML
```
<cac:TaxSubtotal>
  <cbc:TaxableAmount currencyID="EUR">100.00</cbc:TaxableAmount>
  <cbc:TaxAmount currencyID="EUR">20.00</cbc:TaxAmount>
  <cac:TaxCategory><cbc:ID>S</cbc:ID><cbc:Percent>19</cbc:Percent></cac:TaxCategory>
</cac:TaxSubtotal>
```

## Affected Fields

- [BT-116 VAT category taxable amount](/resources/xrechnung/bt-116-vat-category-taxable-amount)
- [BT-117 VAT category tax amount](/resources/xrechnung/bt-117-vat-category-tax-amount)
- [BT-118 VAT category code](/resources/xrechnung/bt-118-vat-category-code)
- [BT-119 VAT category rate](/resources/xrechnung/bt-119-vat-category-rate)

## Related Rules

- [BR-S-1](/resources/kosit-validator-errors/br-s-1-standard-rated-line-requires-standard-rated-vat-breakdown)
- [BR-S-8](/resources/kosit-validator-errors/br-s-8-standard-rated-taxable-amount-must-match-line-and-allowance-sum)
- [BR-CO-18](/resources/kosit-validator-errors/br-co-18-vat-breakdown-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.