For organisations trading in Poland, or invoicing Polish customers, this is not simply a formatting change. It represents a structural shift in how invoices are issued, delivered, received, and stored. The Polish tax administration will play an active role in invoice exchange through a centralised clearance style model.

Mandatory adoption began in 2026, with phased implementation dates based on taxpayer size and turnover thresholds.

Transalis is supporting customers in preparing for these changes through managed compliance services, integration support, and ongoing transaction handling to ensure a smooth transition into the new regulated environment.

Following a voluntary phase which started in 2022 for B2B transactions, the Polish authorities have introduced mandatory B2B invoice reporting via their online system, Krajowy System e-Faktur (KSeF).

In this blog, we outline the requirements applicable to those operating in Poland and how we can help businesses meet this new eInvoice mandate.

Poland has been phasing in eInvoice regulations for several years, similar to many other European countries.

Krajowy System e Faktur (KSeF) is Poland’s national eInvoicing system, operated by the Ministry of Finance and the National Revenue Administration. Under this model, invoices are issued in a structured electronic format and submitted directly into the government platform. Once processed, the invoice becomes the official version for both the supplier and the buyer. The Polish government defines KSeF as a system used for the issuing, receiving, and storage of structured invoices (faktury ustrukturyzowane).

Official overview:
https://ksef.podatki.gov.pl/co-to-jest-ksef/

Poland is adopting a centralised clearance style framework. This differs from traditional invoicing models where invoices are exchanged directly between trading partners.
In practice, the process operates as follows:

This approach increases transparency and provides the tax administration with near real time access to invoice data. The Ministry also provides for specific operational modes, including online and offline invoicing scenarios. Special invoicing modes guidance:
https://ksef.podatki.gov.pl/informacje-ogolne-ksef-20/tryby-szczegolne-wystawiania-faktur/

Poland has confirmed that mandatory B2B eInvoicing will be introduced in phases. The key implementation dates are:

These dates are confirmed in official KSeF legal timeline publications.

Key dates and legal basis:
https://ksef.podatki.gov.pl/informacje-ogolne-ksef-20/podstawy-prawne-oraz-kluczowe-terminy/

SME and sole trader guidance:
https://ksef.podatki.gov.pl/krok-po-kroku-jdg-i-msp/

KSeF is being introduced as part of Poland’s broader VAT compliance and invoicing reform programme. Structured invoices submitted through KSeF will become the legally recognised invoice format once the mandate applies. This is a significant compliance requirement for businesses operating within scope. The Ministry of Finance has also published implementing regulations supporting the operational rollout of KSeF.

Regulatory updates from the Ministry of Finance:
https://www.gov.pl/web/finanse/rozporzadzenia-wykonawcze-do-krajowego-systemu-e-faktur

Poland’s KSeF model effectively functions as invoice level clearance and reporting, because invoice data is transmitted directly into the government platform rather than exchanged only between supplier and buyer.

This is distinct from separate post transaction reporting regimes in other jurisdictions, but it does mean that businesses must treat KSeF submission as a regulated compliance step, not just an electronic delivery method.

For many organisations, this will require changes to:

With mandatory adoption beginning in 2026, impacted organisations should begin readiness planning now.
Key steps include:

The Polish government also provides official taxpayer tools and platform documentation, but many businesses will require scalable integration and support beyond the basic portal functionality.

Taxpayer application information:
https://ksef.podatki.gov.pl/aplikacja-podatnika-ksef-20/

Transalis provides end to end support for organisations impacted by Poland’s mandatory eInvoicing reforms.

Our service helps customers:

Poland has adopted regulated digital invoicing, and the system is already live. Transalis helps organisations become fully compliant with the mandate requirements by providing secure, scalable eInvoicing solutions that integrate seamlessly with existing ERP and finance systems. Our expertise ensures smooth onboarding, minimal disruption, and ongoing compliance as regulations evolve, reducing risk while enabling businesses to operate confidently in Poland’s digital tax environment.

If your organisation is not yet compliant with the mandates, Transalis can help you achieve full compliance quickly and efficiently with secure, scalable eInvoicing solutions tailored to your requirements.