The introduction of the National e-Invoice System (KSeF) represents the most fundamental change in the national economic system since the introduction of the Standard Audit File (SAF), digitizing a key business process. This obligation will apply to a broad range of businesses from April 1, 2026. Although the reform is national in nature, its implementation raises significant questions and potential challenges for companies operating internationally. Understanding the new rules is crucial not only for regulatory compliance but also for maintaining the smooth and efficient operation of trade relations with foreign partners.
2.0 Asymmetry of Responsibilities: The Key Difference Between Inbound and Outbound Invoicing
The principle governing the KSeF in international trade is the asymmetry of obligations, which depends on the direction of the transaction. In practice, this means that the way Polish entrepreneurs receive invoices from foreign entities remains unchanged. If a foreign counterparty is not identified for VAT purposes in Poland and does not have a Polish Tax Identification Number (NIP), the documents they issue are not subject to registration with the KSeF. These invoices can still be sent in traditional format, for example, as a PDF file via email or in hard copy.
The situation is completely different when a Polish entrepreneur issues an invoice to a foreign contractor. Because Polish lawmakers have jurisdiction over Polish taxpayers, the regulations in this area are stringent and constitute the core of the challenges associated with implementing the National Tax and Customs Code. Understanding this dichotomy is the starting point for properly implementing the new obligations incumbent on Polish exporters.
When and how to issue an invoice to a foreign contractor?
For Polish entrepreneurs acting as sellers, the rule is clear: the obligation to use the KSeF system is determined by their status as a Polish VAT payer. In practice, this means that almost every invoice documenting the export of goods or intra-Community supply of goods (ICS) must be passed through the KSeF system.
This approach creates a double burden for the Polish entrepreneur. The invoice must be generated in a structured format (XML) and properly submitted to the KSeF for approval and assignment of an identification number. However, because the foreign buyer has no technical or legal access to the KSeF, the Polish seller must provide them with access to the document in another way. Several methods of invoice delivery are possible:
◦ sending a visualization of the invoice in PDF format.
◦ delivery of a traditional paper invoice.
◦ providing a link containing a visualization of the invoice with a QR code that allows it to be displayed.
To sum up, the basic rule requires a Polish entrepreneur to issue an invoice to a foreign contractor via KSeF, unless the transaction is covered by one of the statutory exclusions.
When is KSeF not required in foreign transactions?
The obligation to use the KSeF is not absolute, and the legislator has provided several important exceptions that directly apply to international trade. Understanding these exclusions, defined in Article 106ga, Section 2 of the VAT Act, is crucial for optimizing processes and avoiding unnecessary administrative burdens. Polish entrepreneurs are exempt from the obligation to issue a structured invoice in the following cases:
• sales to foreign individuals not conducting business activity. In transactions with a foreign consumer, an invoice may be issued and delivered directly to the customer in paper or electronic form, completely bypassing the KSeF.
• sales under special EU procedures. The obligation does not apply to transactions settled under the VAT One-Stop-Shop (VAT OSS) procedure and other EU procedures.
In both situations, Polish entrepreneurs avoid the need to generate a structured invoice, significantly simplifying the process. While these statutory exemptions offer some simplification, in most B2B transactions, Polish exporters will have to face a new, dual-track operational reality that brings with it a number of challenges.
Key operational challenges:
Polish companies will be forced to simultaneously use KSeF for domestic reporting purposes and maintain traditional communication channels (e-mail, post) to deliver invoices to foreign partners.
It may be necessary to explain the specifics of the new invoice format to foreign recipients. This is an opportunity to build trust by providing clear instructions on how to read the document (e.g., using a QR code visualization) and addressing any formal concerns.
Furthermore, larger trading partners using automated systems may perceive the need to manually process invoices in non-standard formats as a risk. Transparent communication and collaborative solution development will be crucial.
It's also important to remember that the EU's ViDA (VAT in the Digital Age) package stipulates that all member states will use structured invoices by 2030, and that EU countries' systems will be synchronized in 2035. Therefore, there's a high probability that your partner's country already uses structured invoices, or is preparing to implement the system in your country.
Ultimately, mastering the KSeF in international trade is not just a technical task but also a test of operational efficiency and strategic foresight. Proactive preparation, especially during the initial period of new regulations, is a key lever for minimizing the risk of disruption.
This article is for informational purposes only and does not constitute legal advice.
The law is current as of February 2, 2026.
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