KSeF and Self‑Billing – Approval Must Precede Submission to KSeF

KSeF and Self‑Billing – Approval Must Precede Submission to KSeF

Individual ruling: 0112‑KDIL1‑3.4012.874.2025.2.KK (27 February 2026)

The Polish tax authorities have issued an important individual interpretation clarifying how self‑billing processes must operate under mandatory KSeF, in particular the timing of supplier approval and the consequences for VAT deduction. The ruling is highly relevant for large taxpayers entering mandatory KSeF from 1 February 2026 and working with subcontractors subject to KSeF at a later stage. [eureka.mf.gov.pl]

Background of the case

A Polish VAT‑registered company used self‑billing to invoice services supplied by subcontractors, based on contractual authorisation under Article 106d of the Polish VAT Act.
With the introduction of mandatory KSeF, the company asked whether it could:

• submit a self‑billing invoice to KSeF first, and
• obtain the supplier’s approval only afterwards,
  without jeopardising VAT deduction.

As an alternative, the company proposed a pre‑approval workflow using PDF draft invoices (without KSeF number, invoice number or issue date), followed by submission to KSeF.

Position of the tax authority

The Director of the National Tax Information (KIS) rejected most of the taxpayer’s position and took a strict procedural approach to self‑billing under KSeF. [eureka.mf.gov.pl]

1. Approval after KSeF submission – not allowed

The authority ruled that supplier approval must take place before the invoice is issued in KSeF.
Submitting the invoice to KSeF first and approving it afterwards breaches Article 106d VAT Act, as the approval procedure is a condition for valid issuance of a self‑billing invoice. [eureka.mf.gov.pl]

2. VAT deduction denied if approval is late

If supplier approval occurs after the invoice has already been submitted to KSeF, the invoice is considered defective, and the buyer cannot exercise the right to deduct VAT on that basis. [eureka.mf.gov.pl]

3. PDF draft approval without KSeF data – also rejected

The authority also rejected the proposed workaround whereby suppliers would approve PDF draft invoices lacking:

• KSeF number,
• invoice number, and
• invoice issue date.

Such drafts do not qualify as invoices under the VAT Act and therefore cannot form a valid approval basis for self‑billing prior to KSeF submission. [eureka.mf.gov.pl]

4. Correction after KSeF submission – allowed

The only point accepted by the authority concerns post‑submission corrections.
If errors are identified after a self‑billing invoice has been correctly issued and approved, the buyer must issue a structured correcting invoice in KSeF (rather than cancelling and re‑issuing the original invoice). [eureka.mf.gov.pl]

Practical implications for businesses

This ruling confirms a formalistic and sequential interpretation of self‑billing under KSeF:

• Supplier approval is a precondition, not a post‑issuance formality.
• Internal workflows must ensure approval before KSeF submission.
• “Draft invoice” concepts without mandatory invoice data are not recognised.
• Errors after issuance must be handled via KSeF corrections, not re‑issuance.

For multinational groups and shared service models, this significantly impacts process design, automation, and controls, especially where suppliers enter KSeF later than the buyer.

Summary – 3 key takeaways

• Approval first, KSeF second: Self‑billing invoices must be approved by the supplier before submission to KSeF. [eureka.mf.gov.pl]
• VAT deduction at risk: Late approval invalidates the invoice and blocks VAT deduction. [eureka.mf.gov.pl]
• No “PDF workaround”: Draft invoices without KSeF and invoice identifiers cannot support valid approval. [eureka.mf.gov.pl]