Glossary EN 16931

EN 16931 is the European standard for the semantic data structure of electronic invoices. It defines a core set of mandatory and recommended fields so that electronic invoices can be exchanged interoperably between different systems and countries and processed automatically. For companies in Germany, EN 16931 is the basis for formats such as XRechnung and the structured XML component of ZUGFeRD/Factur‑X.

Why EN 16931 is important for your accounting

EN 16931 ensures that the invoice data required for tax and commercial law processing are named and structured unambiguously. This has direct effects on:

• VAT: The information on net, tax and gross amounts as well as tax rates must be clearly shown, as required by § 14 UStG.
• Bookkeeping and retention: Electronic invoices must be archived in a way that is audit-proof according to the GoBD; the structured data basis facilitates automated checks and long-term archiving (retention period under the Fiscal Code (AO) and the Commercial Code (HGB): 10 years for tax-relevant documents).
• Automation: Standardized fields enable automatic import into the accounting system, automatic posting suggestions and faster recognition of input VAT.

Concrete requirements and components

EN 16931 defines a Core Invoice Semantic Model (CII) with unambiguous data fields. Particularly relevant in practice are:

• Identification of invoice issuer and invoice recipient (name, address, VAT identification number (USt‑IdNr.)).
• Invoice number and date as well as service or delivery date.
• Breakdown of line items: quantity, description, unit price, net amount.
• Tax information: tax rate, tax amount and tax base for each tax rate.
• Payment terms, bank details (IBAN/BIC) and, where applicable, cash discounts or rebates.

Important: The standard specifies the semantic structure, not the file format. In Germany two practical implementations are common:

XRechnung

The XRechnung is a national implementation of EN 16931, mandatory when sending invoices to public contracting authorities in Germany. For suppliers to federal, state and local authorities, correct use of XRechnung is therefore essential.

ZUGFeRD / Factur‑X

ZUGFeRD (or the international variant Factur‑X) combines a human-readable PDF/A-3 with an embedded EN-16931-compliant XML file. This is practical if you want to support both paper-based processes and machine processing.

Practical examples and use cases in accounting

The following examples show typical situations in which EN 16931 becomes important in daily accounting:

• Freelancer supplies to an authority: The invoice must be submitted as an XRechnung. If a correct invoice number, service period or USt‑IdNr. is missing, processing can be delayed.
• Small business receives structured invoices: Incoming EN-16931-compliant invoices are automatically imported into the accounting software; line items are assigned accounts and input VAT is automatically recognized.
• Archiving and tax audit: In a tax audit, structured invoice data are easier to substantiate; GoBD-compliant storage of the XML data plus PDF makes it easier to demonstrate immutability.

Concrete booking example: The incoming EN-16931 invoice shows net 1,000 EUR, 19% VAT 190 EUR and gross 1,190 EUR. On import the system recognizes the tax coding and automatically posts to the expense account (e.g. 4000) and the input VAT account (1576) according to your chart of accounts.

Implementation steps and checklist for business owners

To ensure EN 16931 works smoothly in your accounting, the following pragmatic procedure is recommended:

1. Check whether you need XRechnung for public contracting authorities and, if necessary, set up export functions.
2. Ensure that your accounting software can import EN-16931/XML or process ZUGFeRD.
3. Validate incoming and outgoing invoices with validators (e.g. XRechnung or ZUGFeRD validators) to detect structural errors early.
4. Implement GoBD-compliant archiving: secure XML plus PDF/A-3, document integrity and access logs.
5. Train employees in the mandatory information under § 14 UStG and the importance of the USt‑IdNr., service date and correct invoice number.

In summary, EN 16931 facilitates machine processing and legal compliance of your invoices. For freelancers and small businesses this means less manual data entry, faster cash discounts and secure archiving — provided the software used and internal processes are adapted accordingly.