Preparations for 1 Feb 2026 e-invoicing mandate: live testing; tokens; regulations pending; updated JPK_VAT
- Poland is entering the final phase of KSeF implementation, with only weeks remaining before the 1 February 2026 mandate.
- Technical progress is significant: the KSeF 2.0 taxpayer app is live
- The main regulation governing KSeF operations has not yet been approved
- Two supporting regulations — on exemptions and invoice issuance — are finalised
- Revised JPK_VAT reporting will also apply from 1 February 2026 – no transitional period.
Poland’s National e-Invoicing System (KSeF) transitions from concept to compulsory reality on 1 February 2026. As the end of 2025 approaches, activity around the programme has intensified, with a rapid succession of technical releases from the Ministry of Finance alongside partial legislative progress. For taxpayers, platforms, and ERP vendors, this creates a mixed picture: operational capability is expanding, but critical regulatory certainty is still lacking.
With fewer than 50 days remaining, businesses are now finalising system builds, completing user acceptance testing, and planning go-live contingencies, often without a complete legislative framework in place. This update summarises the current state of KSeF.
KSeF 2.0 taxpayer application now live with real authentication
In mid-November, the Ministry released a new version of the KSeF taxpayer application, representing the first environment in which users must authenticate using real credentials. This marks a significant step change from the long-running test environment, which allowed logins using any valid NIP.
However, the shift also exposed operational risks. Shortly after launch, a number of real invoices were issued in the test environment using genuine supplier and customer data. Their subsequent removal required direct Ministry intervention, prompting the introduction of additional warnings instructing users and software providers to rely strictly on anonymised test data. For businesses running parallel testing or high-volume UAT cycles, this incident highlights the need for disciplined test-data controls and clearly segregated environments.
Token-based authentication (MCU) finally available
From 8 December, taxpayers can generate API authentication tokens within the Ministry’s MCU, providing a long-awaited alternative to KSeF certificates. This development is particularly important given the launch date: 1 February 2026 falls on a Sunday, increasing the risk of system pressure in the days immediately beforehand.
While certificates remain valid, token-based access is expected to become the preferred method for direct integrations with KSeF. Businesses should now be validating token creation, expiry, renewal, and revocation within their ERP or tax engine, as well as confirming that role-based authorisation models reflect operational responsibilities.
Legislative status: partial progress, but the core regulation remains stalled
The legal framework for KSeF is spread across several separate regulations. Two of these have now completed the approval process and are ready for publication.
Regulation on exemptions
This regulation introduces several clarifications, including:
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Confirmation that taxpayers benefiting from an exemption may still voluntarily issue structured invoices via KSeF.
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Clear differentiation within financial and insurance services: invoices using a reduced data set fall outside the mandate, while those requiring the full schema must be issued through KSeF.
Regulation on invoice issuance
This regulation formalises invoice content in line with the KSeF schema, confirming mandatory data fields for domestic supplies, intra-EU transactions, and special VAT schemes.
Key limitation: the main KSeF operational regulation remains unresolved
The central regulation governing system operation and day-to-day use is currently stalled in the Legal Committee. With less than two months remaining before go-live, this delay leaves unresolved questions around certain processes, including elements of error handling, corrections, and workflow execution. Any late publication or amendment will have immediate and potentially disruptive operational consequences. Continuous monitoring is therefore essential.
JPK VAT changes confirmed from day one — no transition period
In parallel, the Ministry has confirmed that the revised JPK_VAT structure will apply in full from 1 February 2026, with no transitional relief. Industry proposals to limit additional reporting tags, reduce scope, or phase in requirements were rejected.
As a result, taxpayers must implement KSeF alongside expanded JPK obligations simultaneously. This significantly raises the compliance bar, requiring tightly aligned data mapping, validation rules, and reconciliation processes between invoicing, VAT determination, and reporting systems from day one.
Final thoughts before KSeF-day
With technical capability accelerating but legislative certainty still incomplete, businesses face a compressed and high-risk implementation window. Organisations now need to prioritise final integration testing, confirm authentication approaches, and ensure their reporting frameworks can support both KSeF and JPK changes in parallel — while remaining alert to last-minute regulatory developments that could materially affect compliance processes at launch.
