Reference
Markdown exportBT-21 Invoice note subject code
Code that classifies the subject of an invoice note.
Quick answer
Invoice basics
Core document identifiers, dates, process identifiers, and high-level invoice context.
Quick actions
In plain language
Code that classifies the subject of an invoice note.
Code that classifies the subject of an invoice note.
Use this only when the invoice note should be machine-classified instead of being plain free text.
What you usually enter here
Approved note subject code
Typical valid values include: AAI
Optional according to EN 16931-1. If provided, use the approved code list.
What goes wrong often
Avoid values like: note
Examples in context
Use this only when the invoice note should be machine-classified instead of being plain free text.
Optional according to EN 16931-1. If provided, use the approved code list.
Valid Examples
- AAI
Invalid Examples
- note
XML mapping and field facts
Open the technical reference if you need XML paths, validator rule codes, legal wording, or schema-specific mapping details.
Field ID:
BT-21
Data Type:
code
Cardinality:
0..1
Requirement:
Optional
Max Length:
10 characters
Since Version:
Optional
XML Implementation
Not used in Peppol BIS Billing 3.0 UBL Invoice (BT-21 cardinality is reduced to 0..0)./CrossIndustryInvoice/ExchangedDocument/ram:IncludedNote/ram:SubjectCodeNext step
Create an XRechnung from your PDF
The converter reads the invoice and shows the fields it found before download, so you can check and correct the values. No PDF? Fill in the XRechnung directly in the form.
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Why the standard cares about this field
Business Context
Use this only when the invoice note should be machine-classified instead of being plain free text.
Legal Requirement
Optional according to EN 16931-1. If provided, use the approved code list.