Germany's E-Invoice 2027: the 12-point readiness check for the Mittelstand

April 2026, month-end close at a mid-size German machinery manufacturer. The CFO calls. Eight input-VAT reversals in the first quarter alone. One of his suppliers has been sending invoices labelled “E-invoice” in the header since January — all of them PDFs without embedded XML. The accounting team typed them in manually, as always. At the VAT reconciliation, they failed: the German Ministry of Finance letter from 25 October 2025 makes it explicit that a PDF without EN 16931-conformant XML is not an e-invoice in the VAT sense — and the input VAT deduction is denied if the supplier is already subject to the mandate.

From 01 January 2027, exactly this constellation becomes the obligation for German Mittelstand companies with previous-year turnover above 800,000 euro. Whoever fails to run a pilot in 2026 will accumulate either broken contracts with large customers or input-VAT reversals on the receiving side in 2027 — typically both. Either effect, let alone the combination, costs more than three months of implementation work.

This article delivers the 12-point self-check you can run this week, plus a pilot calendar covering May to December 2026.

What changes on 01 January 2027

The legal baseline has been fixed since the Wachstumschancengesetz of 27 March 2024. The Ministry of Finance letter from 25 October 2025 then concretised the application guidelines.

The receiving obligation for structured e-invoices has been in force since 01 January 2025 for all domestic B2B recipients, regardless of turnover. This obligation has been practice for over a year — but in many Mittelstand firms only formally, because operational workflows still rely on humans reading PDF content while ignoring the embedded XML.

The sending obligation phases in over two stages. From 01 January 2027 it applies to all domestic B2B turnover, when the previous-year turnover of the issuer exceeds 800,000 euro. From 01 January 2028 it applies without any turnover threshold. EDI procedures without EN 16931 conformance are permitted only until 31 December 2027.

The 800,000 euro threshold refers to the previous year, not the current year. A manufacturer with 850,000 euro turnover in 2026 must issue structured invoices from 01 January 2027. A trade business with 750,000 euro turnover in 2026 has one additional year and must send from 01 January 2028.

Format reality, May 2026

The accepted formats have evolved since the rollout.

XRechnung is pure XML and currently runs in version 3.0.2. KoSIT released the last bugfix bundle on 31 January 2026. XRechnung 4.0 is announced as a major release for mid to late 2026 — the key change concerns the ability to bundle multiple purchase orders and deliveries in one invoice.

ZUGFeRD is a hybrid format combining PDF/A-3 with embedded XML. The current version 2.4 was published on 04 December 2025 and is in force since 15 January 2026. Critically, not all ZUGFeRD profiles meet the requirements for the sending obligation. Profiles MINIMUM and BASIC-WL deliver too little structured data and are therefore unsuitable for automated accounting processing. The recommended profiles are EN 16931 (also called COMFORT) and EXTENDED.

The format reality one year after the receiving obligation shows that a large share of ZUGFeRD invoices is sent in profiles MINIMUM or BASIC, with validation errors and ERP import failures. Whoever builds their sending now has the advantage of starting in the right profile from day one.

The 12-point self-check

These twelve questions are the minimum you should be able to answer this week. Whoever cannot clarify one of them has a project assignment for June 2026.

1. Am I subject to the sending obligation from 01 January 2027?

Previous-year turnover 2026 above 800,000 euro means yes. The basis is the VAT turnover under UStG, not the balance-sheet turnover under HGB. For holding structures and partnerships, the calculation is to be checked individually per VAT-registered invoice issuer.

2. Can I receive e-invoices?

The receiving obligation has been in force since 01 January 2025. Operationally that means a simple email inbox is not enough. You need at minimum an XML parser, GoBD-compliant archiving of the XML file (not only the PDF view), and a workflow that imports the XML into accounting.

3. What format does my ERP produce today?

Most ERP systems can produce ZUGFeRD or XRechnung. The decisive factor is the profile. Ask your ERP vendor to confirm in writing that at least ZUGFeRD 2.4 in profile EN 16931 is produced. Profiles MINIMUM and BASIC-WL do not meet the 2027 sending obligation.

4. Does accounting process the XML automatically?

A common practice pattern: a ZUGFeRD PDF arrives by email, the accounting team opens the PDF, reads the visible invoice and types the data into ERP manually. The embedded XML is ignored. This workflow is tolerable in 2026 and a compliance risk from 2027 onwards, because in reversal cases nobody can locate the XML.

5. Do I have sender-side validation before dispatch?

There is no mandatory sender validator, but the Ministry of Finance letter from 25 October 2025 explicitly recommends validation before dispatch. Workable options are the KoSIT validator (official, free) or commercial validation services. Sender-side checks reduce returns by 60 to 80 percent.

6. Do I archive the XML in a GoBD-compliant way?

§ 14b UStG requires you to retain a copy of every invoice for eight years. For e-invoices, the structured component (the XML) must be preserved unaltered in its original form. A viewer-generated PDF derived from the XML is not enough. The XML file itself must be archived.

7. Is there a pilot plan?

See the calendar below. Whoever fails to pilot during May to July 2026 has no reserve left for iteration and training.

8. Does my ERP vendor have XRechnung 4.0 and ZUGFeRD 2.4 on the roadmap?

Ask for the concrete roadmap. ZUGFeRD 2.4 has been productive since 15 January 2026, XRechnung 4.0 is coming mid to late 2026. Anyone still on XRechnung 3.0.2 in Q4 2026 and waiting for the upgrade should have a plan B.

9. How many incoming invoices are currently “other invoices”?

Quantify your input-VAT risk. When a supplier becomes obliged to send structured invoices in 2027 but instead sends you a PDF, you lose the deduction. If 20 percent of your incoming invoices today do not arrive in structured format, that is a material risk from 2027 onwards.

10. Which large customers will demand e-invoices from 2027?

DAX and MDAX corporations, banks and insurers typically pull the requirement forward. Suppliers to those customers should ask by Q3 2026 from when the recipient accepts only structured e-invoices. Early pilot partners are gold here.

11. Is accounting trained on XML import?

PDF reading is not enough. Accounting and tax teams must operate the XML import, interpret validation errors, and formulate correction requests to suppliers. A half-day training in autumn 2026 is the minimum.

12. Build or buy: own pipeline or service?

Multiple routes are realistic. An ERP vendor module is often included in the maintenance contract. A specialised e-invoicing service (Stedi, Validoo, Crossinx and others) outsources validation and archiving. Your own pipeline based on the KoSIT open-source tools works for IT-affine Mittelstand firms. For smaller volumes, pure SaaS offerings are also viable. Above 50,000 incoming invoices per year, a service comparison pays off. For DATEV-connected setups, watch the DATEV interface roadmap, which has historical pitfalls of its own.

Pilot calendar, May through December 2026

Starting earlier creates reserve for unforeseen vendor issues in the autumn. Starting in October 2026 leaves no such reserve.

The two counter-lobbies that miss the point

Lobby 1 — “We’re under 800,000 euro, this doesn’t concern us in 2027.” This reading blends out the chain risks. The receiving obligation has applied to all companies regardless of turnover since 01 January 2025, and in many Mittelstand firms still does not work operationally. Large customers above the threshold will exert pressure on their suppliers to deliver in structured format from 2027 onwards. And the full obligation from 01 January 2028 covers all B2B turnover without any exception. Small size buys you a maximum of 18 months delay, not two years and not indefinitely.

Lobby 2 — “Our ERP can already do all of this.” The vendor statement is formally accurate, but in practice it fails at several points. The productive ZUGFeRD profile is often MINIMUM or BASIC-WL rather than EN 16931 or higher. A sender-side validation pipeline does not exist in many ERP installations. GoBD-compliant archiving of the XML next to the PDF is sometimes configured but rarely audited. Accounting and tax teams are trained on reading PDFs, not on importing XML. Ask the ERP vendor to confirm in writing which profiles are productively supported and which validation mechanisms are built in. A statement like “we can do ZUGFeRD” is not enough.

Frequently asked questions

We’re at 750,000 euro turnover — do we really have two more years?

Sending obligation begins for you on 01 January 2028, which is one year after the larger Mittelstand. Receiving obligation already applies to you since 01 January 2025. Whoever accepts a PDF instead of an e-invoice as a recipient, once the supplier is obliged to send structured invoices, risks input-VAT reversals.

Is a ZUGFeRD PDF from our ERP enough?

Only at profile EN 16931 (COMFORT) or higher in ZUGFeRD from version 2.0 onwards. MINIMUM and BASIC-WL meet the formal norm but are unsuitable for automated accounting and not named as sufficient in the Ministry of Finance letter. The recommendation is ZUGFeRD 2.4 with profile EN 16931 or EXTENDED.

What happens if we’re not ready to send on 01 January 2027?

Large customers with their own compliance pressure will push you as a supplier. For contracts with formal invoice-approval rules, the recipient may formally refuse payment. The tax office does not impose direct fines, but your customers’ input-VAT deduction is at risk, which damages the customer relationship.

Which validator is mandatory?

There is no mandatory sender validator. The recommendation is the KoSIT validator (official, free, via xeinkauf.de) and the ELSTER e-invoice viewer of the German tax administration (e-rechnung.elster.de). Both validate against the EN 16931 schema. Sender-side validation before dispatch reduces returns and is explicitly recommended in the Ministry of Finance letter from 25 October 2025.

Do we need to archive the XML separately, or is the PDF enough?

You must retain the structured XML part in a GoBD-compliant way, not only the PDF view. § 14b UStG requires eight years of retention in unaltered form. A viewer-generated PDF derived from the XML is not enough, because the XML file must be preserved as the source artefact.

Is a 2026 pilot worth it if we are only obliged from 2028?

Yes. The receiving obligation already applies, and the first large customer that becomes obliged to send in 2027 forces your accounting into the XML mode. Without that capability, expect late payments and reversals. A pilot in 2026 is cheaper than an emergency rollout in 2027.

Next step

If you walk through the 12-point self-check and answer “don’t know” to more than three items, the conversation does not start with a proposal. It starts with a free 60-minute sparring session. You bring the completed self-check. I bring the action logic. The outcome is your call.

For the topic fields I work in, see my advisory for compliance and mandatory topics and ERP projects and systems. Direct contact: rene@pfisterer.xyz or through the contact form.

Seven months is enough for a clean pilot. Every month lost halves the reserve for the inevitable autumn iteration.