BR-CL-23 Invalid unit code (e.g. “Stk”)

In the invoice data the unit must not be a word (“Stk”, “hrs”, “lump sum”) but a code from the UN/ECE list. The PDF can still show “pcs”.

The message in the validation report

[BR-CL-23] Unit code MUST be coded according to the UN/ECE Recommendation 20 with Rec 21 extension

Common causes

• The software copies its own unit names into the XML.
• Outdated or look-alike codes (e.g. “PCE”, “STK”).

How to fix it

1. Switch units to codes. Most common: H87 piece · C62 unit · HUR hour · DAY day · MTR metre · MTK m² · MTQ m³ · KGM kg · LTR litre · LS lump sum · SET set · XPK package · XRO roll/coil.
2. Many programs have an “e-invoice code” or “UN/ECE” field in the unit settings.

What it should look like (XRechnung, CII syntax)

<ram:BilledQuantity unitCode="H87">4</ram:BilledQuantity>   <!-- Stück -->
<ram:BilledQuantity unitCode="HUR">2.5</ram:BilledQuantity> <!-- Stunden -->

Want to read or check an invoice you received? Open XRechnung · Check invoice

More error codes

• BR-DE-15Leitweg-ID / buyer reference missing
• BR-DE-1Payment instructions missing
• BR-DE-2Seller contact missing (also BR-DE-5, -6, -7)
• BR-DE-21Not an XRechnung (wrong specification identifier)
• BR-DE-23-aCredit transfer without IBAN
• BR-DE-18Skonto (cash discount) in the wrong format
• BR-CO-10Sum of line amounts does not match
• BR-CO-15Gross total is not net plus VAT
• BR-S-08VAT breakdown per rate does not match

Guides to German e-invoicing

• Open an XRechnung and save it as PDF
• ZUGFeRD or XRechnung: which one do I need?
• E-invoices for small businesses under § 19 UStG
• Sending an XRechnung to a German authority

Rule text from the official KoSIT validation rules (XRechnung 3.0.2, EN 16931). General technical explanation, not tax or legal advice.