Date in Field P_1 Is Invoice Issue Date for VAT Purposes, Not KSeF Creation Date

• The date of issuance of an e-invoice is the date in field P_1, not the date the invoice is created in KSeF.
• This date (in field P_1) is also the date when the tax obligation arises, if it matches the delivery date.
• The tax authority confirmed that for invoices in foreign currency, the exchange rate should be based on the date in field P_1.
• The company’s practice of issuing invoices with the tax obligation date, even if sent to KSeF later due to logistical delays, was fully accepted by the tax authority.
• 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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