# BR-CO-13

> Invoice total amount without VAT (BT-109) must equal Sum of line net amounts (BT-106) minus document-level allowances (BT-107) plus document-level charges (BT-108). Check cbc:TaxExclusiveAmount against those components.

Checked against Peppol BIS Billing 3.0 2026.5

Canonical: https://einvoicecheck.eu/rules/br-co-13

## Official rule text

Invoice total amount without VAT (BT-109) = Σ Invoice line net amount (BT-131) - Sum of allowances on document level (BT-107) + Sum of charges on document level (BT-108).

## Why did my invoice fail BR-CO-13?

The Invoice total amount without VAT (BT-109) must equal the sum of all Invoice line net amounts (BT-131) minus the sum of document-level allowances (BT-107) plus the sum of document-level charges (BT-108). This ties the taxable-basis total to the underlying lines and document-level adjustments so the invoice foots correctly before VAT is applied.

## Common causes

- BT-109 (LegalMonetaryTotal/TaxExclusiveAmount) hard-coded or copied from a source system instead of recomputed from the lines.
- A document-level allowance or charge (AllowanceCharge on the invoice) is not reflected in the AllowanceTotalAmount / ChargeTotalAmount used for the total.
- Rounding each line to 2 decimals but summing unrounded line values (or vice versa), causing a 0.01 mismatch.
- One or more Invoice line net amounts (cbc:LineExtensionAmount) are wrong or omitted.

## How do I fix it?

```
Compute TaxExclusiveAmount = Σ line LineExtensionAmount − AllowanceTotalAmount + ChargeTotalAmount. E.g. lines 100.00 + 50.00, allowance 10.00, charge 5.00 → <cbc:TaxExclusiveAmount currencyID="EUR">145.00</cbc:TaxExclusiveAmount>.
```