BR-DE-16

As soon as the invoice uses one of the tax category codes S, Z, E, AE, K, G, L or M, the seller must be identifiable for tax: through a VAT identifier (BT-31), a tax registration identifier (BT-32), or a tax representative (BG-11).

Severity: Error
Applies to: CII, UBL
Rule set: v2026-01-31

Official rule text

Wenn in einer Rechnung die Steuercodes S, Z, E, AE, K, G, L oder M verwendet werden, muss mindestens eines der Elemente "Seller VAT identifier" (BT-31), "Seller tax registration identifier" (BT-32) oder "SELLER TAX REPRESENTATIVE PARTY" (BG-11) übermittelt werden.

Why it happens

Small businesses under § 19 UStG use category E and often have no VAT identifier. The tax number is frequently missing too, because the previous invoice layout never captured it.

How to fix it

Supply at least one of the three. Without a VAT identifier, BT-32 (tax registration number) is the usual choice.

NormAPI provides technical validation, not tax or legal advice.