# BR-DE-12 Invoice must have at least one invoice line

An invoice must have at least one invoice line.

## Problem Description

An invoice must have at least one invoice line.

> **ERROR**: XRechnung 3.0

## Context and Significance

An invoice without line items cannot be validated consistently and does not represent billable goods/services. Even if you invoice a single total, provide at least one line with the billed item or service.

## Solution

Add at least one invoice line to the invoice.

## Valid Examples

- One InvoiceLine representing a service fee
- Multiple lines with items/services

## Invalid Examples

- No <cac:InvoiceLine> elements at all

## Code Examples

### Valid XML
```
<cac:InvoiceLine>
  <cbc:ID>1</cbc:ID>
  <cbc:InvoicedQuantity unitCode="C62">1</cbc:InvoicedQuantity>
  <cbc:LineExtensionAmount currencyID="EUR">100.00</cbc:LineExtensionAmount>
  <cac:Item><cbc:Name>Service fee</cbc:Name></cac:Item>
  <cac:Price><cbc:PriceAmount currencyID="EUR">100.00</cbc:PriceAmount></cac:Price>
</cac:InvoiceLine>
```

### Invalid XML
```
<!-- Missing cac:InvoiceLine -->
```

## Technical Details

### Affected Fields
Invoice Lines

## 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.