# BR-IC-08 Intra-community taxable amount must equal the net sum

In a VAT breakdown (BG-23) where the VAT category code (BT-118) is "Intra-community supply", the VAT category taxable amount (BT-116) shall equal the sum of invoice line net amounts (BT-131) minus document level allowance amounts (BT-92) plus document level charge amounts (BT-99) whose VAT category codes (BT-151, BT-95, BT-102) are "Intra-community supply".

## Problem Description

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

## Context and Significance

This calculation rule ties the intra-community taxable base to the underlying lines, allowances and charges. The K amount is also reported in the VAT return and the recapitulative statement, so it must be arithmetically correct. In practice, the gap appears when freight or a discount with category K is left out of BT-116.

## Solution

Recompute BT-116 for the K breakdown as Σ BT-131 − Σ BT-92 + Σ BT-99 over all K-category lines, allowances and charges, and write that value into TaxableAmount.

- [Validate XML](/en/xrechnung-validator?source=resource&rule=BR-IC-08)
- [Convert invoice](/en/pdf-to-xrechnung?source=resource&rule=BR-IC-08)

## Valid Examples

- Two K lines of 600.00 and 400.00 with no adjustments give BT-116 = 1000.00

## Invalid Examples

- K lines summing to 1000.00 but BT-116 declared as 950.00

## Code Examples

### Valid XML
```
<cac:TaxSubtotal>
  <cbc:TaxableAmount currencyID="EUR">1000.00</cbc:TaxableAmount>
  <cbc:TaxAmount currencyID="EUR">0.00</cbc:TaxAmount>
  <cac:TaxCategory>
    <cbc:ID>K</cbc:ID>
    <cbc:Percent>0</cbc:Percent>
    <cac:TaxScheme><cbc:ID>VAT</cbc:ID></cac:TaxScheme>
  </cac:TaxCategory>
</cac:TaxSubtotal>
```

### Invalid XML
```
<cac:TaxSubtotal>
  <cbc:TaxableAmount currencyID="EUR">950.00</cbc:TaxableAmount>
  <cbc:TaxAmount currencyID="EUR">0.00</cbc:TaxAmount>
  <cac:TaxCategory>
    <cbc:ID>K</cbc:ID>
    <cbc:Percent>0</cbc:Percent>
    <cac:TaxScheme><cbc:ID>VAT</cbc:ID></cac:TaxScheme>
  </cac:TaxCategory>
</cac:TaxSubtotal>
```

## Affected Fields

- [BT-116 VAT category taxable amount](/resources/xrechnung/bt-116-vat-category-taxable-amount)
- [BT-131 Invoice line net amount](/resources/xrechnung/bt-131-invoice-line-net-amount)
- [BT-118 VAT category code](/resources/xrechnung/bt-118-vat-category-code)

## Related Rules

- [BR-IC-09](/resources/kosit-validator-errors/br-ic-09-vat-amount-must-be-zero)
- [BR-IC-01](/resources/kosit-validator-errors/br-ic-01-intra-community-vat-breakdown-required)
- [BR-CO-18](/resources/kosit-validator-errors/br-co-18-vat-breakdown-required)

## 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.