What Is an E-Invoice — and Why Isn't a PDF One?

Posted on August 21, 2026

← Back to Pillar: E-Invoicing in Germany for Freelancers and Small Businesses Related articles: ZUGFeRD or XRechnung? · The 2025–2028 decision tree

PDF, ZUGFeRD or XRechnung?: Three invoice formats compared: a PDF sent by email is only a picture and not an e-invoice. ZUGFeRD is a PDF with an embedded XML file, readable by people and software. XRechnung is a pure XML file for software. The XML part is always the legally binding one.

An e-invoice is an invoice whose content comes in a structured, machine-readable format that follows the European standard EN 16931 — in Germany mainly XRechnung and ZUGFeRD (version 2.0.1 or later). Software can read the invoice number, amount, VAT rate and sender directly, without guessing. A normal PDF sent by email, on the other hand, is just a picture of the invoice and has counted as an "other invoice" (sonstige Rechnung), not an e-invoice, since 2025.

The difference in one sentence

A PDF is made for people; an e-invoice is made for people and software. With a PDF, someone has to type the numbers or a text-recognition tool has to guess them. With an e-invoice, they're in the file as data — unambiguous, no room for interpretation.

The three variants you'll come across

PDF by email: looks like an invoice but contains no structured data. Not an e-invoice.
ZUGFeRD: a PDF with an embedded XML file containing all invoice data. You see the familiar invoice; software reads the data. The XML part is the legally binding one.
XRechnung: a pure XML file with no visual layout. Without a suitable program you only see code.

More on choosing between the two formats: ZUGFeRD or XRechnung — Which Format Do You Need?

Why the legislator wants this

Structured invoices can be checked, booked and — eventually — reported to the tax authorities automatically. As an invoice recipient, that means less typing and fewer typos for you. As an invoice issuer, it means your data has to be complete and correct from the start, because software doesn't forgive a missing VAT ID.

Real-world example

An IT consultant was told by a client that his invoice was "not an e-invoice". He was surprised — it was electronic, a PDF by email. That's the most common misunderstanding: "sent electronically" isn't the same as "e-invoice". Only when he started generating his invoices as ZUGFeRD could his client's accounts department process them automatically.

What you can do now

Open the last invoice you received from a larger supplier (phone, hosting, software). Does your PDF reader show file attachments? If you find a file like factur-x.xml or zugferd-invoice.xml, you're already holding a ZUGFeRD e-invoice.

FAQ

Is a scanned invoice an e-invoice? No. A scan is a picture, just like a PDF without embedded data.

Can I convert a normal PDF into an e-invoice afterwards? Only by regenerating the invoice with structured data. The data has to come from your invoicing tool, not from the finished PDF.

Does this also apply to invoices to consumers? No. The e-invoicing obligation covers invoices between businesses in Germany.

Note: This article is not tax advice. The binding sources are the German Federal Ministry of Finance and your IHK (chamber of commerce) (both in German); for your specific case, ask your tax advisor.

All of it in 13 pages: Get our free booklet E-Invoicing, Compact as a PDF – with the decision tree, a mistakes check and a switch-over plan – and receive the SmoovOps newsletter. → Get the booklet