E-Invoicing Becomes Mandatory: The Issuing Obligation from 2027 – How SMEs Should Switch Now

The e-invoice is no longer a thing of the future – it has been rolling out for a while now, just in stages. Since the start of 2025, every business must be able to receive e-invoices. The second, bigger step is now on the doorstep: the obligation to issue e-invoices yourself. For many companies in the Ruhr region it begins as early as 1 January 2027. This post puts the deadlines in order and shows what your accounting needs to have in place by then.

Note: This article is not tax or legal advice. It frames the situation and names first steps. What is binding is your individual circumstances – when in doubt, speak to your tax advisor. As of: June 2026.

What an e-invoice actually is

The most important misconception first: a PDF invoice sent by email is not an e-invoice in the legal sense. A genuine e-invoice contains the invoice data in a structured, machine-readable format compliant with the European standard EN 16931 – that is, data a piece of software can read and process directly, without anyone retyping it. The classic PDF, by contrast, counts as an "other invoice."

Two formats are common and permitted in Germany:

• XRechnung – a pure XML format, technical, with no visible layout.
• ZUGFeRD from version 2.0.1 – a hybrid: a normal-looking PDF with the structured data embedded inside it. To the human eye it looks like a PDF invoice, yet it is still machine-readable for software. (The slim MINIMUM and BASIC-WL profiles do not meet the requirements on their own.)

For businesses that want to keep "seeing" their invoices, ZUGFeRD is usually the more comfortable route in practice.

The deadlines at a glance

The obligation applies only in the B2B sphere – that is, to invoices between domestic companies. Invoices to private customers are not affected.

• Since 1 January 2025: Every domestic B2B business must be able to receive e-invoices. An email inbox is legally sufficient for this – the recipient's consent is not required.
• From 1 January 2027: Obligation to issue for companies with more than €800,000 in turnover in the previous year (2026).
• From 1 January 2028: The issuing obligation applies to all remaining B2B businesses – regardless of turnover.

So until the end of 2027, smaller businesses (up to €800,000 in prior-year turnover) may still send paper or PDF invoices. But take note: this concerns only the issuing. You already have to receive structured invoices today – and your larger customers may send them to you entirely routinely from 2027.

Why you should not wait until December 2027

Three sober reasons argue against putting it off:

1. You already receive e-invoices. Anyone who merely collects them in the inbox and does not process them properly risks losing input VAT and creating chaos in their accounting – the GoBD (Germany's principles for the proper keeping of digital records) require audit-proof storage in the original format.
2. Software providers and advisors will be booked out in 2027. If everyone switches at the same time, it gets tight. A calm transition now is cheaper and less error-prone than a last-minute scramble just before the deadline.
3. The switch improves your processes. Structured invoices can be checked, assigned and posted automatically. What begins as an obligation ends up saving real working time.

The first concrete steps

Here is how to approach the topic pragmatically – without an expensive specialist solution if you don't need one:

1. Secure receiving. Set up a dedicated invoice inbox (e.g. invoice@yourcompany.de) and make sure incoming XRechnung and ZUGFeRD files reliably land there and are made visible.
2. Take stock of your software. Can your invoicing, ERP or accounting program create and read XRechnung or ZUGFeRD? Many common programs can already do so, or can with an update – the feature is just often not switched on.
3. Clean up your master data. Structured invoices are stricter than PDFs: routing IDs (Leitweg-ID), correct tax numbers/VAT IDs, clean product and customer data. Gaps that nobody notices in a PDF will make an e-invoice fail technically.
4. Sort out audit-proof storage. The structured file is the original and must be retained in a GoBD-compliant way – not the pretty printout.
5. Coordinate with your tax advisor. How does the data reach them, in which format, by which route? Clarifying this interface early saves duplicate work later.

Common pitfalls

• "Surely the PDF is enough." From the respective cut-off date, no longer – the structured data has to be present.
• Isolated solutions. Anyone writing invoices in Excel or an old Access database has no clean path to the e-invoice. Here it pays to look at a lean, integrated solution.
• Thinking only about issuing. Receiving is already mandatory and is easily overlooked.
• Format profiles. Not every ZUGFeRD profile is permitted – pay attention to version and profile.

Conclusion

The e-invoice is arriving reliably and in clear stages: receiving since 2025, issuing from 2027 for larger businesses and from 2028 for all B2B companies. That is no reason to panic, but a good occasion to set up your invoicing processes cleanly for once – instead of doing it under time pressure in December 2027. Done right, the switch means less bureaucracy and more automation.

Not sure whether your software is already ready, or what your path to the e-invoice looks like? In a free initial consultation we'll look at your processes together and find the leanest route – level-headed and with no sales pressure.