E-Invoicing Mandate: A Roadmap for German SMEs

Since January 1, 2025, every company in Germany has been required to be able to receive and process electronic invoices — regardless of size, sector, or revenue. That obligation is already in force, even though it barely registers yet in the daily routine of many mid-market companies. The confusion usually comes down to mixing up two different deadlines: one for receiving invoices, one for sending them. Anyone who thinks there’s still time until 2027 or 2028 is usually only thinking about the sending side. Receiving is already mandatory.

What looks at first glance like another piece of tax-law bureaucracy actually touches almost every department: accounting, purchasing, sales, and IT all need to pull in the same direction so that invoices don’t just arrive, but get processed automatically and archived in a legally sound way. This article sorts out the deadlines, explains the difference between XRechnung and ZUGFeRD, and walks through what actually matters for ERP integration and archiving.

What Actually Counts as an E-Invoice?

The term gets misused constantly in everyday business. A PDF invoice sent by email is electronic, but it is not an e-invoice in the legal sense. Under the new definition, an e-invoice is a structured electronic format compliant with the European standard EN 16931, built to be processed automatically without anyone retyping the data by hand.

Everything else — paper invoices and PDFs without structured data — now falls under the category of “other invoice” (sonstige Rechnung). That distinction is the core of the entire reform: from a certain point onward, an “other invoice” will no longer be sufficient for domestic B2B transactions, no matter how well it’s formatted or how reliably it has worked so far.

Two formats have become established in Germany, both of which can comply with EN 16931: XRechnung and ZUGFeRD. More on those below.

The Legal Timeline at a Glance

The reform isn’t arriving all at once — it’s being phased in. That takes pressure off the rollout, but it also makes the legal picture harder to track, since different rules apply to different companies at different points in time.

Date	What applies
since January 1, 2025	Receiving obligation: every domestic company must be able to receive and technically process e-invoices, regardless of size
until December 31, 2026	Transition period for sending: “other invoices” (paper, PDF) may still be issued with the recipient’s consent
until December 31, 2027	Extended transition period for companies with prior-year revenue below €800,000
from January 1, 2028	Full mandate: e-invoices must be both issued and received in domestic B2B transactions

The first row of that table is the one that matters most. It applies to every company immediately, while the following transition periods only govern the sending side. A small trades business with two million euros in annual revenue can still send its customers a PDF invoice until the end of 2026 — but it already has to be able to accept and process an XRechnung from a supplier today. This is exactly where many companies get caught out: they never look at the receiving side because they’re focused on the more comfortable sending deadline that applies to them.

XRechnung and ZUGFeRD: Two Roads to the Same Destination

Both formats meet the legal requirements, but they differ significantly in structure and practical usability.

XRechnung is a purely structured XML format. Without dedicated viewer software, it’s practically unreadable for humans — something many accounting teams still need to get used to. XRechnung first became established in the public sector: companies that already invoice government agencies are often familiar with the format from that work.

ZUGFeRD takes a hybrid approach: at its core, it’s a PDF/A-3 document with an embedded XML file. The invoice remains directly readable for humans, while accounting software can automatically extract the embedded structured data. For many mid-market companies, this is the more pragmatic entry point, since it largely preserves the familiar invoice layout.

One important detail: ZUGFeRD comes in several profiles, and only the profiles that fully comply with EN 16931 satisfy the legal requirements for an e-invoice. Older or stripped-down profiles don’t qualify. Before rolling anything out, it’s worth checking the fine print of your own invoicing software.

Which format ends up in use often depends less on your own preference than on what your business partners require. Larger customers or public-sector clients sometimes mandate a specific format.

What This Means for ERP and Accounting Software

The transition is primarily a software question — but not one that can be left to the IT department alone. Most established ERP and accounting systems have already added, or announced, modules for sending and receiving e-invoices. The sensible first step is a conversation with your software vendor: which format is supported, from when, and what will the update cost?

The receiving side is trickier. An incoming XRechnung can’t simply be printed and filed away — it needs to be read in, validated, and fed into the accounting workflow by machine. Without that automation, you end up with exactly the extra work the law was meant to eliminate: someone has to manually turn structured data back into something readable before it can be checked and approved.

For companies that process a high volume of incoming invoices, this is a good occasion to rethink the whole accounts-payable process: automatic matching against purchase orders, digital approval workflows, a clean handoff into the payment run. The e-invoicing mandate provides the external trigger — the real value comes from a well-designed, largely automated process behind it.

GoBD-Compliant Archiving: The Structured Data Is What Counts

One point gets overlooked regularly in practice: legally, what matters for a ZUGFeRD invoice is the structured XML file, not the human-readable rendering. A company that only archives the PDF view and discards the embedded XML file may well be archiving the wrong version — with real consequences if a tax audit ever asks for it.

Archiving has to meet the familiar GoBD principles: the data must remain complete, unalterable, and machine-readable for the entire statutory retention period. During a tax audit, authorities need reasonably prompt access to the original data, not just a printout. If you already run a document management or archiving system, check specifically whether it correctly stores structured XML data long-term, or whether it needs an extension to do so.

It’s also worth putting together a short process document: how do e-invoices enter the company, how are they validated, where are they stored, who has access? That sounds like paperwork for its own sake, but it’s exactly what protects you the moment an audit starts asking questions about the process.

Common Pitfalls for Mid-Market Companies

Mixing up the deadlines. The receiving obligation has applied to every company since January 2025. Only sending is staggered. Companies that rely on the transition periods running to 2026 or 2027 easily overlook that their trading partners may already be required to deliver structured invoices today.

Assuming a PDF is good enough. Even a beautifully formatted PDF invoice is not an e-invoice under the law once the relevant transition period has expired. Without embedded or accompanying structured data, it lacks the machine-readability the law requires.

Skipping technical validation of incoming invoices. Structured formats follow strict schemas. Without validation in place, faulty invoices go unnoticed or get silently rejected by the receiving system.

Leaving approval workflows unchanged. When an invoice arrives as a data record instead of paper or a PDF, the existing approval workflow often needs rework — including the basic question of who actually gets to see the structured data.

Treating it as an IT-only project. The technical implementation matters, but accounting, purchasing, and sales all need to buy into the new workflows. Without their involvement, even the best system goes unused.

Recommended Steps

1. Take stock. How many invoices do you issue per month, how many do you receive, and in what formats does that run today?
2. Talk to your software vendor. Ask specifically about the roadmap for e-invoicing features in your ERP or accounting system, and what it will cost.
3. Decide on a format. Check whether customers or suppliers expect a particular format, then choose between XRechnung and ZUGFeRD.
4. Build the receiving process. Make sure incoming e-invoices can be automatically validated, parsed, and pulled into your accounting system.
5. Check your archiving. Confirm that your archive system stores the structured original data in a GoBD-compliant way for the full retention period.
6. Bring your team along. Inform accounting, purchasing, and sales early about the new workflows, and document the process.

Conclusion: No Reason to Rush, but None to Wait Either

The staggered deadlines give companies time to plan the transition properly instead of scrambling at the last minute. That time should still be used, though — the receiving obligation is already here, and ignoring it simply means incoming invoices pile up or need manual rework. Companies that treat this as an opportunity to overhaul their entire invoicing process will come out the other side with a cleaner, more automated workflow than they started with.

Want to get your ERP landscape ready for the e-invoicing mandate and automate accounts payable at the same time? We help you choose the right interfaces and build an end-to-end, GoBD-compliant process.

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