How do I fix IS-R-001?

Invoice Navigator automatically fixes this Invoice compliance issue by updating the relevant XML elements (IS-R-001). You can also use Invoice Navigator's compliance engine to correct this automatically in your pipeline.

Is IS-R-001 a critical error?

Yes, IS-R-001 is a critical error that will cause invoice rejection. It must be fixed before submission.

Can IS-R-001 be automatically fixed?

Many instances of IS-R-001 can be automatically corrected using Invoice Navigator's compliance engine. The fix is applied in your pipeline with full audit evidence.

errorISLCIUS-IS (Iceland)

`IS-R-001`:Icelandic suppliers can only issue invoice type 380 (invoice) or 381 (credit...

Icelandic suppliers can only issue invoice type 380 (invoice) or 381 (credit note). Other document types are not supported for Icelandic e-invoicing.

Severity

Fatal

Rule set

CIUS-IS (Iceland)

Country

ISL

Fix type

AUTO-FIX

Confidence

75%

Engine Classification

Ensure Icelandic seller registration identifier is present

Confidence: 75% · Applied automatically in pipeline

What is IS-R-001?

IS-R-001 is a fatal validation rule defined in the CIUS-IS (Iceland) specification (ISL national rules). It validates the CompanyID element under Party > PartyLegalEntity in the UBL invoice XML.

When this rule fires, the invoice is non-compliant and will be rejected by Peppol access points and national validation services. The sending system receives a rejection response and the invoice does not reach the buyer.

Target path: //cac:AccountingSupplierParty/cac:Party/cac:PartyLegalEntity/cbc:CompanyID

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Why This Error Matters

Invoice will be rejected by Icelandic validation. Only standard invoices and credit notes are supported.

IS-R-001 is a hard failure. Invoices that trigger this rule are rejected at the access point and never reach the recipient. In Peppol networks, this means your sending system receives an MLR (Message Level Response) with a rejection status. The invoice must be corrected and re-sent, adding delay to your payment cycle.

Invoice Navigator can automatically correct this error in your pipeline. The fix is applied with full audit evidence, so your compliance trail remains intact.

Validator Behavior

·Causes invoice rejection
·Error returned: IS-R-001
·Specification: CIUS-IS (Iceland)

Before / After

Failing XML

<Invoice>
  <!-- Issue: If seller is Icelandic then invoice type should be 380 (invo -->
</Invoice>

Corrected XML

<Invoice>
  <!-- Issue resolved per CIUS-IS (Iceland) -->
</Invoice>

Technical Reference

XPath//cac:AccountingSupplierParty/cac:Party/cac:PartyLegalEntity/cbc:CompanyID

SpecCIUS-IS (Iceland)

Operationset_default

StrategyEnsure Icelandic seller registration identifier is present

Common Causes

·Wrong invoice type code used
·Proforma or other document type selected
·Invoice type not set correctly
·ERP default type not valid for Iceland
·Document type from non-Icelandic template

Seeing this in production? The API handles IS-R-001 automatically. See the fix response →

Related Errors

IS-R-002

Icelandic suppliers must provide their Icelandic legal ID (kennitala). This...

IS-R-003

Icelandic suppliers must provide complete address with street name and...

IS-R-004

When both seller and buyer are Icelandic, the buyer's kennitala must be...

Last updated: 27 February 2026

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Handle IS-R-001 Automatically in Your Pipeline

The compliance engine auto-remediates this error with controlled safety policies and evidence pack generation.

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IS-R-001:Icelandic suppliers can only issue invoice type 380 (invoice) or 381 (credit...