# BR-CL-01 Invoice type code must come from UNTDID 1001

The document type code (BT-3) must be a value from the invoice and credit-note code lists of UNTDID 1001.

## Problem Description

The document type code (BT-3) must be a value from the invoice and credit-note code lists of UNTDID 1001.

> **ERROR**: XRechnung 3.0

## Context and Significance

This EN16931 core code-list rule ensures the document type is machine-readable across all receiving systems.

## Solution

Set BT-3 to a valid UNTDID 1001 code, e.g. 380 (commercial invoice), 381 (credit note), 384 (corrected invoice), 389 (self-billed invoice) or 875-877 (construction invoices).

- validate
- convert

## Valid Examples

- BT-3 = 380 — commercial invoice
- BT-3 = 381 — credit note

## Invalid Examples

- BT-3 = 999 — not part of UNTDID 1001
- BT-3 = INV — free text instead of a code

## Code Examples

### Valid XML
```
<cbc:InvoiceTypeCode>380</cbc:InvoiceTypeCode>
```

### Invalid XML
```
<cbc:InvoiceTypeCode>999</cbc:InvoiceTypeCode>
```

## Affected Fields

- [BT-3 Invoice type code](/resources/xrechnung/bt-3-invoice-type-code)

## Related Rules

- [BR-CL-06](/resources/kosit-validator-errors/br-cl-06-untdid-2005-vat-point-date)

## 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.