Tax Authority Confirms: E-Invoice Issue Date Is Field P_1, Not KSeF Creation Date

• The tax authority confirms that the invoice issue date is the date in field P_1 of the structured e-invoice, not the date the invoice is created in the KSeF system.
• This date (P_1) determines when the tax obligation arises, especially when the invoice date matches the delivery date.
• For invoices in foreign currency, the tax base can be converted using the NBP exchange rate from the last business day before the invoice issue date (P_1).
• The tax authority fully accepted the company’s approach, which aligns the invoice date with the moment the tax obligation arises, even if the invoice is sent to KSeF later due to logistical delays.
• The company is preparing to use KSeF from February 1, 2026, issuing structured invoices in its accounting system and sending them to KSeF via dedicated software.

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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