OIOUBL
OIOUBL is Denmark’s adaptation of the OASIS Universal Business Language for electronic business documents such as invoices and credit notes. Danish authorities publish profiles, guidelines, code lists, and validation material around its use. A file being XML or UBL-like does not by itself make it valid OIOUBL or acceptable to a recipient; the relevant profile and business rules still matter.
Why this matters when you invoice
An invoice can be valid XML and still miss the profile, business rules or code-list requirements that apply to an OIOUBL exchange. Separating syntax from the applicable specification helps prevent false confidence from a file that merely opens correctly.
Where it appears
OIOUBL appears in Danish guidance for structured invoices, credit notes and other business documents and is closely connected to NemHandel workflows.
Which OIOUBL version is actually in use
Erhvervsstyrelsen cancelled OIOUBL 3.0 in early 2026 before it became mandatory. Danish invoices in circulation today use OIOUBL 2.1 (in use until its planned phase-out in 2029) or Peppol BIS Billing 3, and Denmark is moving to NemHandel BIS 4 from 2028. A file labelled OIOUBL is most likely OIOUBL 2.1, not OIOUBL 3.0.
Readable XML is only one layer
A supplier receives an OIOUBL invoice file and can inspect its seller, buyer, lines and totals. That inspection does not establish that every required profile rule, code list or recipient requirement has been satisfied; those validations remain separate.
Common mistakes
- Calling every UBL invoice OIOUBL.
- Assuming XML that parses successfully is profile-compliant.
- Confusing the OIOUBL document specification with NemHandel network delivery.
View supported OIOUBL XML
Use the XML viewer to inspect supported invoice fields and deterministic preflight findings.
InvoiceCraftly can display supported OIOUBL XML in its viewer, but it does not certify OIOUBL profile compliance or deliver the file through NemHandel. The viewer currently maps the cancelled OIOUBL 3.0 profile at the field level; an OIOUBL 2.1 file (what most Danish invoices use today) is recognized as generic UBL without full field mapping.
Official references
- NemHandel — Guidance and OIOUBL documentation
- Meridian — Denmark cancels OIOUBL 3.0
- Fiscal Requirements — NemHandel BIS 4 roadmap
Sources and terminology reviewed 5 September 2026. Next evidence review: 4 December 2026.
Frequently asked questions
Is OIOUBL the same as generic UBL XML?
No. OIOUBL applies Danish profiles, guidance and business rules to UBL-based electronic business documents.
Can InvoiceCraftly inspect OIOUBL XML?
The XML viewer can display supported OIOUBL XML, but it does not certify the file against the relevant OIOUBL profile or recipient requirements.