E-Invoice Error Reference

KSEF-007 is raised when a date or timestamp in an FA(2)/FA(3) e-invoice does not match the format the KSeF (Krajowy System e-Faktur) XSD requires. The Polish schema uses two different date types: plain calendar dates such as P_1 (data wystawienia / issue date), P_6 (sale date) and the due date must be xs:date in YYYY-MM-DD form, while DataWytworzeniaFa (the technical document creation timestamp in the header) must be a full xs:dateTime with a UTC time-zone designator. Any other shape — a localised 15.04.2026, a slash date, a two-digit year, a date-only value placed in DataWytworzeniaFa, or a timestamp missing its Z / +02:00 offset — is rejected before the business checks even run.

errorBR-PL-02POLksefBLOCKED

Invalid KSeF invoice type

Polish KSeF invoices must use valid invoice type codes.

errorKSEF-002POLKSeFBLOCKED

Invoice date too old for KSeF

Invoice issue date cannot be more than 30 days before KSeF submission date. Older invoices will be rejected by the system.

errorKSEF-003POLKSeFBLOCKED

Invoice number sequence gap

Invoice numbers must be sequential without gaps within each calendar year. KSeF rejects invoices with numbering gaps or duplicates.

warningPL-R-007POLubl-2.1INPUT

Split payment annotation required

High-value Polish invoices may require split payment notation.

errorPL-R-005POLubl-2.1INPUT

Invalid Polish NIP format

Polish NIP must be 10 digits with valid checksum.

errorKSEF-006POLKSeFINPUT

Unit code not recognized

Unit of measure must be from Polish classification. Common codes include szt. (piece), kg, m, l, usł. (service).

warningKSEF-008POLKSeFINPUT

GTU code missing

Certain goods/services require GTU (Grupy Towarów i Usług) classification codes. Required for alcohol (GTU_01), fuel (GTU_02), heating oil (GTU_03), tobacco (GTU_04), and other specific categories.

errorBR-PL-01POLpeppol-bis-3INPUT

Polish NIP number required

Polish invoices must include the NIP (tax identification number) for seller and buyer.

errorKSEF-004POLKSeFINPUT

Currency code invalid

Currency must be a valid ISO 4217 code. Use PLN for domestic invoices.

errorKSEF-001POLKSeFINPUT

KSeF NIP validation failed — bad format or wrong identifier field

KSEF-001 fires when a Polish tax identification number (NIP) on a KSeF e-invoice is malformed or placed in the wrong identifier element. A NIP must be exactly 10 digits and pass the official weighted check-digit test; the KSeF schema field that carries it (Podmiot1/Podmiot2 → DaneIdentyfikacyjne → NIP) accepts digits only — no PL prefix, no spaces, no dashes. A second, very common variant is putting a domestic NIP in the EU VAT field (NrVatUE) or a generic identifier (NrID) instead of the NIP element, which both fails validation and breaks routing of the invoice to the correct party inside KSeF.

errorKSEF-005POLKSeFINPUT

KSeF VAT rate invalid — StawkaPodatku not in the Ministry of Finance dictionary

KSEF-005 is raised when a VAT rate or tax category on an FA(2)/FA(3) invoice does not match the values the KSeF schema and the Ministry of Finance dictionary allow. KSeF does not accept arbitrary percentages or free-text descriptions: each line's rate must map to an allowed value (currently 23%, 8%, 5%, 0%) or to one of the markers — zw (exempt), np (out of scope), and the reverse-charge handling — declared through P_12 and consistent with the document totals (P_13_x / P_14_x). A non-dictionary percentage, or a marker inconsistent with the amounts reported for that group, is rejected.

warningPL-01POLCIUS-PL (Poland)BLOCKED