A unique identification of the Invoice. The identification scheme shall provide uniqueness within the business relationship between the Seller and the Buyer.
The invoice number serves as the primary identifier for the invoice and is essential for accounting, payment processing, and legal compliance. It must be unique within the business relationship.
Mandatory according to EN 16931-1. German tax law (UStG) requires invoices to have consecutive numbering within one or more series.
/Invoice/cbc:ID
/CrossIndustryInvoice/ExchangedDocument/ram:ID
INV-2024-001
RE20240327001
R-2024-03-15-001
2024-INV-12345
F-20240327-001
✗ Invalid
✗ InvalidINV 001
✗ InvalidINV/001/2024
✗ InvalidYes, the invoice number only needs to be unique within the business relationship between you and each specific customer.
German tax law requires consecutive numbering within one or more series. The numbering system must be designed to prevent gaps and duplicates.
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