KSEF-005:VAT rate invalid for item type
Polish VAT rates (23%, 8%, 5%, 0%, ZW-exempt, NP-not subject) must match item classification rules per Polish VAT law and PKWiU classification.
Engine Classification
Financial or legal field · Modification blocked by policy
Reason: The VAT rate applied does not match Polish VAT law requirements for this item type. VAT rates (23%, 8%, 5%, 0%, ZW, NP) are determined by PKWiU product classification. Review the item classification in your source system and apply the legally correct VAT rate. Consult Polish VAT regulations or a tax advisor if uncertain.
What is KSEF-005?
KSEF-005 is a fatal validation rule defined in the KSeF specification (POL national rules). It checks whether vat rate invalid for item type.
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.
Why This Error Matters
KSEF-005 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.
Validator Behavior
- ·Causes invoice rejection
- ·Error returned: KSEF-005
- ·Specification: KSeF
How to Fix It
Technical Reference
Code Example
<StawkaPodatku>23</StawkaPodatku>Common Causes
- ·Wrong rate for product category
- ·Rate changed by new legislation
- ·Misclassified goods/services
Seeing this in production? The API handles KSEF-005 automatically. See the fix response →
Frequently Asked Questions
Polish VAT rates (23%, 8%, 5%, 0%, ZW-exempt, NP-not subject) must match item classification rules per Polish VAT law and PKWiU classification.
Verify VAT rate matches Polish VAT law for the item type. This error involves a protected field — Invoice Navigator flags it in your pipeline so your team can correct it at the source.
Yes, KSEF-005 is a critical error that will cause invoice rejection. It must be fixed before submission to ensure your invoice is accepted by the recipient's system.
KSEF-005 involves a financial or legal field that cannot be auto-modified by policy. Invoice Navigator detects and flags this error immediately, but the correction must be made manually in your ERP or invoicing software.
Related Content
Last updated: 3 March 2026
Detect KSEF-005 Before Submission
This error involves a financial or legal field that cannot be auto-modified. The compliance engine flags it immediately with a clear diagnosis so your team can fix it at the source.