Is Your Company Ready for KSeF Offline Mode? Key Test Before Mandatory Launch in 2026

• The National e-Invoice System (KSeF) becomes mandatory for Polish companies on February 1, 2026.
• A complete technical shutdown of KSeF is planned from January 26 to 31, 2026, during which issuing, receiving, and downloading invoices will be impossible.
• This shutdown is a test of companies’ ability to operate offline, not a test of the system itself.
• Experts advise companies to audit their API integrations, establish emergency procedures, and ensure offline certification before January 26 to avoid business paralysis.
• After February 1, 2026, there will be no margin for error; companies must be fully prepared for this digital transformation.

Source: podatki.gazetaprawna.pl

Note that this post was (partially) written with the help of AI. It is always useful to review the original source material, and where needed to obtain (local) advice from a specialist.

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