Side-by-Side Comparison
| Feature | UBL | CII |
|---|---|---|
| Full Name | Universal Business Language 2.1 | UN/CEFACT Cross-Industry Invoice |
| Maintained By | OASIS | UN/CEFACT |
| Used By | Peppol, XRechnung | ZUGFeRD, Factur-X, XRechnung |
| File Size | Typically larger | Typically smaller |
| Structure | More verbose/explicit | More compact |
| International Adoption | Higher (Peppol network) | Strong in EU (Franco-German) |
What is UBL?
UBL 2.1 (Universal Business Language) is an OASIS standard for business documents. It's verbose but explicit—every element is clearly named and structured.
Used by:
- Peppol BIS Billing 3.0
- XRechnung (UBL variant)
- Many government procurement systems
What is CII?
UN/CEFACT CII (Cross-Industry Invoice) is a UN standard designed for international trade. It's more compact than UBL and widely used in Franco-German trade.
Used by:
- ZUGFeRD
- Factur-X
- XRechnung (CII variant)
Key Differences Explained
1Structure and Verbosity
UBL uses explicit, self-documenting element names. More verbose but easier to read without documentation.
CII uses shorter element names with more nesting. Smaller files but requires documentation reference.
2Ecosystem
UBL dominates international trade (Peppol connects 40+ countries). If you need to invoice globally, UBL is more widely supported.
CII is strong in France and Germany. If most of your trade is Franco-German, CII tools are abundant.
When to Use UBL
- Connecting to Peppol network (required)
- Invoicing internationally
- Working with UK, Nordic, Belgian businesses
- Your ERP exports UBL natively
When to Use CII
- Creating ZUGFeRD or Factur-X invoices (required)
- Trading primarily France/Germany
- Want smaller file sizes
- Your ERP exports CII natively
Can You Use Both?
If you use XRechnung, you can choose either syntax—both are valid. Most implementations pick one and stick with it.
Conversion between UBL and CII is possible since both map to EN 16931, though some edge cases may require attention.
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