KSeF and foreign businesses

Does a foreign company have to issue invoices through Poland’s National e-Invoicing System?

A guide for entrepreneurs and foreign investors | ATL Law 2026

What is at stake

• From 1 January 2027 the grace period ends. Issuing an invoice outside KSeF where the law requires it can trigger a penalty of up to 100% of the VAT shown on that invoice — or up to 18.7% of the gross amount for an invoice with no VAT stated.
• The mandate rolled out in stages: 1 Feb 2026 (large taxpayers, gross sales above PLN 200m; all VAT payers must receive via KSeF), 1 Apr 2026 (all other taxpayers), 1 Jan 2027 (smallest businesses; end of the transitional period).

For a foreign group, the threshold question is different: am I in scope at all?

Two misconceptions foreign groups have about KSeF

Poland’s National e-Invoicing System (KSeF) became mandatory in 2026, reshaping how sales are documented across the market. For a foreign investor the practical question is rarely “how do I use it” but “does it apply to me?” — and here two opposite errors are common.

The first is to treat KSeF as a purely domestic Polish matter that cannot reach a company registered abroad, even one holding a Polish VAT number. The second is the mirror image: assuming that a Polish VAT registration, or a warehouse in Poland, automatically pulls the entity into the full e-invoicing regime. Both are costly. The first risks penalties from 1 January 2027; the second drives unnecessary system-integration spend. The truth sits between them, and it turns on a single VAT concept — the fixed establishment.

The concept that decides everything: the fixed establishment

Whether a foreign taxpayer falls within KSeF depends on whether it has a fixed establishment (FE) in Poland. Polish VAT law does not define the term; the definition sits in Article 11 of Council Implementing Regulation (EU) No 282/2011, under which a fixed establishment is a place — other than the seat of the business — characterised by sufficient permanence and a suitable structure of human and technical resources. The Regulation makes clear that holding a VAT identification number is not, by itself, enough to create an FE.

The decisive practical reference is the Polish Ministry of Finance guidance of 28 January 2026, issued specifically for KSeF purposes (covering the legal state from 1 February 2026). It sets out three conditions that must be met cumulatively:

• human and technical resources — staff and equipment (machinery, systems, and where needed premises) proportionate to the nature of the business;
• a structure capable of supplying services — with emphasis on the establishment’s autonomy from head office and its ability, where needed, to conclude ordinary-course contracts;
• sufficient permanence — a degree of engagement showing the activity is neither transient nor merely occasional.

These criteria track the settled case law of the Court of Justice of the EU and of the Polish administrative courts. No single formal element is conclusive; what matters is the overall picture of the foreign business’s economic presence in Poland.

The statutory test — Article 106ga(2) of the VAT Act

Article 106ga(2) of the VAT Act names who is outside the structured-invoicing obligation. First, taxpayers with neither a seat nor a fixed establishment in Poland. Second, taxpayers with no Polish seat who do have an FE here — provided that establishment does not take part in the supply of goods or services for which the particular invoice is issued.

Read as a sequence: does the entity have an FE in Poland? If not, no obligation arises (voluntary use remains available). If it does, a second question follows: does that establishment actually participate in the transaction being invoiced? Only a “yes” to both creates a KSeF obligation. The assessment is transaction-level, not entity-level — the same company can be obliged for some invoices and exempt for others.

When does the establishment “participate”?

An FE in Poland does not end the analysis. The obligation arises only where that establishment participates in the specific supply. Two typical foreign-investor scenarios show the line.

Example 1. A foreign company runs a staffed logistics centre in Poland that carries out sales of goods to the Polish market. That establishment participates in the supply — the invoices should be issued via KSeF.

Example 2. The same company has a Polish FE but sells software in a model handled entirely by head office abroad, with no involvement of the Polish resources. For those transactions the FE does not participate — no KSeF obligation arises, despite the establishment’s existence.

The lesson is that qualification must be run per transaction, supported by an internal procedure that maps each sale to the resources that in fact performed it.

The compliance timeline at a glance

Five points foreign groups routinely miss

• Invoices to foreign customers still go through KSeF. The exemption is about the issuer, not the buyer. A taxpayer in scope issues via KSeF even to a customer abroad; the foreign buyer usually receives the invoice outside the system, in an agreed form (e.g. a PDF visualisation with a QR code).
• Inbound invoices from foreign suppliers stay out. Documents issued by entities outside KSeF are, as a rule, delivered outside the system — the Polish buyer receives them as before.
• VAT exemption does not remove the KSeF obligation. Entities using a subjective or objective VAT exemption issue via KSeF on general terms where in scope. Business-to-consumer (B2C) invoices, by contrast, remain outside KSeF.
• Granting KSeF authorisations for a foreign entity. Without a Polish qualified signature or seal, granting system permissions electronically can be difficult. The rules allow a paper notification of authorisations for such cases — worth planning ahead of go-live.
• Counterparty risk for the Polish buyer. When dealing with a foreign supplier, the Polish buyer should be clear that the counterparty is correctly invoicing outside KSeF. Commentators consider that an issuer’s misclassification should not, as a rule, cost the buyer its input-VAT deduction — but documenting the position with the counterparty is advisable.

Securing certainty: an individual tax ruling and ongoing review

Given how open-textured the FE concept is and how high the stakes are, the standard safeguard is an application for an individual tax ruling under Article 14b of the Tax Ordinance. A ruling can confirm the absence (or existence) of a fixed establishment and, where one exists, the scope of its participation — while providing legal protection in the event of an audit. That protection tracks the precision of the facts described: a superficial application protects only superficially.

A fixed establishment is also a moving target. Expanding a warehouse, hiring a local sales team, taking effective control of a service provider’s resources, or changing the operating model can create an FE where none existed before. The status should therefore be reviewed periodically, not assessed once on market entry.

Summary and practical recommendations

Whether a foreign company must issue invoices via KSeF is seldom obvious. As a rule, an entity with neither a seat nor a fixed establishment in Poland stays outside the obligation; an FE creates the obligation only where it participates in the particular transaction. Because the FE concept is undefined in statute and assessed holistically, the boundary can be fine.

We recommend three steps: map the group’s economic presence in Poland against the three limbs of the Ministry of Finance guidance; qualify FE participation transaction by transaction; and, where the facts are uncertain, secure the position with an individual ruling before 1 January 2027. This guide is informational; assessing a specific situation calls for individual legal and tax analysis.

About ATL Law

ATL Law is a law firm dedicated to the end-to-end support of foreign investors in the Polish market. We provide multilingual advice (Polish, English, German) in tax, corporate, transfer pricing and employment law. We help clients assess fixed-establishment status, implement KSeF, and obtain individual tax rulings that secure their VAT position.