Date in Field P_1 Is the Official Issue Date for E-Invoices and Tax Obligation, Confirms Tax Office

• The tax authority confirms that the invoice issue date is the date in field P_1 of the e-invoice, not the date the invoice is created in KSeF.
• This date (field P_1) is also the date when the tax obligation arises, if it matches the delivery date.
• For invoices in foreign currency, the tax base can be converted using the NBP exchange rate from the last working day before the invoice issue date in field P_1.
• The tax authority fully accepted the company’s approach, which aligns invoice dates with the moment the tax obligation arises, even if the invoice is sent to KSeF a few days later due to logistical delays.
• The company is preparing for mandatory use of KSeF from February 1, 2026.

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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