# BR-12

> An Invoice shall have the Sum of Invoice line net amount (BT-106).

Checked against Peppol BIS Billing 3.0 2026.5

Canonical: https://einvoicecheck.eu/rules/br-12

## Official rule text

An Invoice shall have the Sum of Invoice line net amount (BT-106).

## Why did my invoice fail BR-12?

The invoice must state the Sum of Invoice line net amounts (BT-106), the total of all line net amounts before document-level allowances, charges and VAT. It is a mandatory total that must equal the sum of each line's BT-131 net amount. In UBL it is cac:LegalMonetaryTotal/cbc:LineExtensionAmount.

## Common causes

- cbc:LineExtensionAmount in LegalMonetaryTotal is missing.
- The element is present but has no value or lacks the currencyID attribute.
- The total was computed but not written to the document total group.
- Line net amounts exist but the document-level sum element was omitted.

## How do I fix it?

```
<cac:LegalMonetaryTotal><cbc:LineExtensionAmount currencyID="EUR">1000.00</cbc:LineExtensionAmount></cac:LegalMonetaryTotal>
```