Poland KSeF News & Updates 2026: Everything That Changed

Poland's KSeF has had a turbulent two years — a failed mandatory launch in 2024, a security overhaul, and now a live mandate. Here is a running log of the key developments.

April 2026 — Full Mandate Now Live for All VAT Payers

1 April 2026 marked the extension of mandatory KSeF to all VAT-registered businesses in Poland, not just large taxpayers.

Key figures from the Ministerstwo Finansów in the first weeks of the full mandate:

Over 95% of eligible businesses had functioning KSeF connections by April 1
Daily invoice volume through KSeF exceeded 1.2 million invoices on the first full mandate day
The KSeF API maintained 99.7% uptime in March 2026 — the stability issues from the 2024 period appear resolved

The Ministry has confirmed that the enforcement team will begin processing non-compliance cases identified during April 2026. Businesses that have not yet connected are strongly advised to contact their accounting software provider immediately.

February 2026 — Large Taxpayer Phase Launched

1 February 2026 — mandatory KSeF began for businesses with annual taxable turnover exceeding PLN 200 million.

The first two weeks had some technical hiccups:

Several large ERP implementations experienced FA(2) schema validation errors due to edge cases in multi-entity invoice structures
The KSeF API experienced a 4-hour partial outage on February 8 — the Ministry invoked the offline mode provisions and confirmed no penalties would apply for invoices correctly issued in offline mode during that window
Software vendors pushed emergency patches; most issues were resolved by February 15

The Ministry of Finance issued a clarification in February 2026 that during the first 90 days of the mandate (February 1 – April 30), penalties would be applied only for deliberate evasion, not technical errors made in good faith during the transition. Evidence of good-faith effort (e.g., logs of attempted API submissions, contact with software vendors) was specified as a mitigating factor.

January 2026 — Final Guidance and Schema Confirmation

The Ministerstwo Finansów published final guidance documents in January 2026:

FA(2) schema frozen for 2026 — The Ministry confirmed that the FA(2) XSD schema would not change before December 2026. Any software using the schema version published in June 2023 (with subsequent minor patches) is compliant. This gave software vendors certainty for the final round of QA.

Self-billing (samofakturowanie) clarification — The Ministry clarified that self-billing invoices under KSeF must be submitted using the seller's NIP credentials, not the buyer's. The buyer acts on behalf of the seller for submission purposes. Software vendors needed to add the appropriate delegation/authorisation support.

Offline mode technical specification — A final technical note confirmed the maximum time window for offline invoice upload is 1 business day from KSeF recovering. The file naming convention for offline invoices was also finalised.

October 2025 — Amended KSeF Act Signed Into Law

The amendment to the KSeF Act (Ustawa o KSeF) setting the February 1 / April 1 2026 mandatory dates was signed by the President and published in the Journal of Laws (Dziennik Ustaw). The law entered into force immediately upon publication.

Key provisions of the amendment:

New mandatory dates as described above
Penalty framework confirmed: up to 100% of VAT amount for non-KSeF invoices
Offline mode requirements codified in law (not just in guidelines)
B2G PEF (Platforma Elektronicznego Fakturowania) remains a parallel obligation for public procurement invoices — KSeF does not replace PEF

What Is Next: Upcoming KSeF Changes

JPK_FA Elimination (Expected 2027)

The separate JPK_FA filing (a SAF-T report of all invoices issued and received) is expected to be eliminated in 2027, since KSeF now provides the same data in real time. The Ministry has indicated this simplification is being worked on, with a target implementation in the JPK regulations by late 2026.

ViDA — EU-Wide E-Reporting (2028)

The EU's VAT in the Digital Age (ViDA) initiative will require digital reporting for cross-border B2B transactions across all EU member states from 2028. Poland's domestic KSeF infrastructure gives it a significant head start — the Ministry has signalled that Poland's cross-border digital reporting will be built on top of the existing KSeF architecture.

B2C Receipts — No KSeF Plans Yet

There is currently no proposal to extend KSeF to B2C transactions (consumer receipts). The separate fiscal receipt (paragon fiskalny) regime with online cashier registers (kasy online) continues for B2C.

FA(2) Schema Update — Planned for 2027

The Ministry has indicated a schema update to FA(3) is planned for 2027, to accommodate ViDA cross-border requirements and to add optional structured payment data fields. FA(2) will remain valid for domestic invoices during any transition.

This page is updated as new KSeF regulatory developments occur. Source: Ministerstwo Finansów — KSeF and podatki.gov.pl/ksef