KSeF Ends Backdating Invoices: VAT Refund Depends on System Date, Not Invoice Date

• The National e-Invoice System (KSeF) eliminates backdating of invoices; the system date, not the invoice date, determines VAT deduction timing.
• VAT refunds may be delayed if invoices are entered late into KSeF, as the right to deduct VAT arises only when the invoice is submitted to the system.
• From February 1, 2026, all entrepreneurs must receive invoices via KSeF.
• In case of internet issues or system failures, the actual receipt date may apply, but strict deadlines for entering invoices into KSeF remain, with penalties for delays.

Source: ksiegowosc.infor.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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