The 2026 revision of EN 16931
What Klarfakt validates today, what the revised standard changes, and what happens to a licence when the new artefacts land.
CEN revised EN 16931 in 2026. If you are considering Klarfakt for something that has to keep working for years, the reasonable question is whether you are buying into a standard that is on its way out.
Short answer: no, and the reason is structural rather than reassuring. Klarfakt does not implement EN 16931. It runs the artefacts the publishers ship. When they publish for the 2026 model, that is a rule pack, not a rewrite.
What Klarfakt validates today
| Pack | Version | Status |
|---|---|---|
cen-en16931 |
1.3.16 | current CEN validation artefacts |
peppol-bis |
3.0.21 | mandatory since 17 August 2026 |
xrechnung |
3.0.2 | current XRechnung release |
schemas |
2026-08-31 | UBL 2.1 and CII D16B as KoSIT redistributes them |
This is what is mandatory now, not what was mandatory when the library was written. Peppol BIS 3.0.21 in particular is the version that became obligatory three weeks before this page was published.
What the revision changes
EN 16931-1:2026 replaces EN 16931-1:2017+A1:2019. It is a substantial expansion rather than a correction: roughly 164 business terms become 216, and 32 business groups become 39.
The additions are aimed at commercial invoicing rather than the public-sector scenarios the 2017 model was designed around — bundled deliveries, invoices spanning several purchase orders, early-payment discounts, default interest, third-party receivables, richer tax-exemption detail, and XML attachments. The strict one order, one delivery, one invoice assumption is gone.
It is also groundwork for ViDA, whose cross-border digital reporting requirements apply from 1 July 2030.
An invoice that passes today’s rules will not necessarily pass the 2026 ones. That is a real migration for whoever issues invoices, and it is worth planning for. It is not a migration you do this quarter.
Why this is not urgent
The two editions run in parallel until 31 March 2029. That is the date by which conflicting national standards must be withdrawn. The 2017 edition remains compliant throughout, and the reference in the Official Journal under Directive 2014/55/EU is still listed as expected rather than published.
The profiles have not moved yet. This is the part that decides what a validator can actually do. Peppol BIS Billing 3.0.21 — the version mandatory today — still describes itself as a CIUS of EN 16931:2017. XRechnung 4.0 was announced by KoSIT in March 2026 and is not released; it depends on CEN delivering the updated syntax bindings to UBL 2.5 and CII D25A, which were only put to a formal vote in July 2026.
So there is currently no XRechnung, no Peppol BIS and no CEN validation artefact for the 2026 model that anyone could run. Not in Klarfakt, and not in the German reference validator Klarfakt is checked against on every build.
What happens when the artefacts land
Klarfakt fetches each pack from its publisher’s pinned release and verifies it against a SHA-256 recorded in the library. Adding a pack is a manifest entry and a new pinned tag. Supporting XRechnung 4.0 alongside 3.0.2 is the same shape of work as supporting XRechnung and Peppol alongside each other today, which the library already does.
Two things follow, and they are the honest limits:
- The 2026 packs will ship as a new rule pack, not a new product. A commercial licence covers every version released during its term, permanently. A licence running when those packs ship includes them.
- The timing is not mine to promise. KoSIT targeted summer 2026 for XRechnung 4.0 and it has not appeared. Klarfakt cannot ship rules that do not exist, and any vendor telling you they are ready for the 2026 model today is describing something they have written themselves rather than the published artefacts.
What is committed is the shape of the response: when a publisher releases, the pack follows, and the comparison against the reference validator has to stay green for it to ship.
If you are starting from scratch
If you are choosing a format now and have no existing invoices to migrate, the common advice is to target the 2026 model directly so the transition cost is paid once. That advice is sound — and it is currently blocked on the same thing everyone else is blocked on, which is that the artefacts are not published.
In the meantime, what you can validate is what your trading partners are actually sending, which is the 2017 model, and will be for some time.