- Effective January 14, 2026, Polish taxpayers intending to use technical attachment nodes for invoices must submit a formal notification to the tax authority, particularly affecting industries like utilities and telecommunications that often include complex billing data. Attachments are restricted to tax-related documents only.
- The current KSeF 1.0 production environment will cease operation on January 26, 2026, with a maintenance blackout period from January 26 to 31, 2026, during which the system will be unavailable. Taxpayers must complete all necessary actions in KSeF 1.0 by January 25.
- The KSeF 2.0 production environment will go live on February 1, 2026, becoming the mandatory system for large taxpayers, requiring businesses to ensure their systems are ready to transition to the new API immediately after the maintenance period to remain compliant.
Source Comarch
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Briefing document & Podcast: Poland E-Invoicing, E-Reporting and KSeF Mandate – VATupdate
- See also
- Join the Linkedin Group on Global E-Invoicing/E-Reporting/SAF-T Developments, click HERE
- Join the LinkedIn Group on ”VAT in the Digital Age” (VIDA), click HERE
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