What it means
The payment and VAT section of the invoice (ApplicableHeaderTradeSettlement) must not contain LetterOfCreditReferencedDocument, a reference to a letter of credit, which is a bank's promise to pay the seller, used mostly in international trade. EN 16931 has no field for it.
Why it matters
This rule is a warning, so the file is still accepted. The reference is outside the standard, so the recipient's software is not expected to read it. It is worth fixing when a recipient or platform wants a file that follows EN 16931 exactly.
How to fix it
Delete the element, or choose the EN 16931 option in the e-invoice export settings of your invoicing software. If the buyer needs the letter of credit number, mention it in an invoice note (BT-22) or agree with them where else to send it.
The rule as published
LetterOfCreditReferencedDocument should not be present Where this rule applies
| Rule set | Version |
|---|---|
| EN 16931 (CII) | 1.3.17 |
| XRechnung 3.0 (CII) | 3.0.2 |
| NLCIUS (CII) | 1.0.3.13 |
| France CTC (CII) | 1.4.0-04 |
Check your file
Drop your e-invoice to see whether CII-SR-424 still fails, and which other rules do.