> ## Documentation Index
> Fetch the complete documentation index at: https://docs.formepdf.com/llms.txt
> Use this file to discover all available pages before exploring further.

# E-invoicing (Factur-X / ZUGFeRD)

> Render the invoice PDF and embed your EN 16931 XML as a validated PDF/A-3 e-invoice container — in one pass.

A hybrid e-invoice (Factur-X in France, ZUGFeRD in Germany) is a PDF/A-3
file that people can read, carrying a machine-readable EN 16931 invoice XML
as an embedded attachment. Forme builds the **container**: you supply the
XML, Forme renders the human-readable PDF and embeds the XML conformantly
in the same render call.

```tsx theme={null}
import { renderDocument } from '@formepdf/core';
import { standardFonts } from '@formepdf/fonts-standard';

const pdf = await renderDocument(
  <Document pdfa="3b" pdfUa lang="de-DE" fonts={standardFonts()}>
    <Page size="A4" margin={50}>{/* your invoice layout */}</Page>
  </Document>,
  {
    facturX: {
      xml: invoiceXml,        // your EN 16931 CII XML (string or bytes)
      profile: 'EN 16931',    // MINIMUM | BASIC WL | BASIC | EN 16931 | EXTENDED | XRECHNUNG
    },
  },
);
```

## What Forme handles

* **PDF/A-3** (`pdfa: "3b"`, `"3u"`, or `"3a"`) — identical to PDF/A-2 plus
  permission for arbitrary embedded files. 3b is sufficient for every
  Factur-X profile.
* The attachment as a conformant **associated file**: spec filename
  (`factur-x.xml`; `xrechnung.xml` for the XRECHNUNG profile), MIME type
  `text/xml`, `/F`/`/UF`, `/AFRelationship` (profile-derived: `Data` for
  MINIMUM/BASIC WL, `Alternative` otherwise; overridable), `/Params` with a
  deterministic `ModDate`, and the catalog `/AF` association.
* The **Factur-X XMP identification** (`fx:` extension schema with
  DocumentType, DocumentFileName, Version, ConformanceLevel) plus the
  PDF/A extension-schema description that makes it legal.
* **Composition with PDF/UA-1** — an invoice can be archival, accessible,
  and machine-readable at once (`pdfa="3a" pdfUa`).
* **Validation in CI**: every commit renders this exact configuration and
  gates it on veraPDF (PDF/A-3b + PDF/UA-1) *and*
  [Mustangproject](https://www.mustangproject.org/), the ZUGFeRD/Factur-X
  reference validator. Evidence: [parity.formepdf.com](https://parity.formepdf.com).

## What Forme does not do

Forme does **not** generate or validate EN 16931 semantic content. The
invoice XML — its \~170 business terms, tax categories, and the 300+
business rules over them — comes from you (your ERP, billing system, or an
EN 16931 library). A conformant container around a non-conformant XML is
not a legal e-invoice; validate your XML with Mustang or the
[CEN validation artefacts](https://github.com/ConnectingEurope/eInvoicing-EN16931).

Also worth knowing: under the German B2B mandate, `MINIMUM` and `BASIC WL`
profiles do **not** count as e-invoices (they lack line items) — use an
`EN 16931`-profile XML for legal compliance in Germany, and `EN 16931` or
`EXTENDED` for France.

## Generic attachments

The same machinery is available without the e-invoice framing — any file,
under PDF/A-3 or plain PDF:

```tsx theme={null}
const pdf = await renderDocument(doc, {
  attachments: [
    { name: 'source-data.csv', data: csvBytes, mimeType: 'text/csv', relationship: 'Source' },
  ],
});
```

Under PDF/A-**2**, attachments are refused with a named error: part 2 only
permits other PDF/A files as attachments (ISO 19005-2 §6.8), which Forme
cannot verify — a file that lies about conformance is worse than none.
Use `pdfa: "3b"` or drop the conformance claim.