Poland: Mandatory B2B Electronic Invoicing as of February 2026
Poland activates mandatory B2B electronic invoicing with KSeF from February 2026
On February 1, 2026, the Polish Ministry of Finance launched the first mandatory phase of B2B electronic invoicing through KSeF, affecting approximately 4,200 large taxpayers.
The second phase will begin on April 1, 2026, for most companies, while micro-enterprises will have to comply from January 1, 2027.
B2B electronic invoicing in Poland
Poland is moving forward with the mandatory implementation of B2B electronic invoicing through the National Electronic Invoice System (KSeF), a centralized platform managed by the Ministry of Finance.
The legal framework, initially announced in 2021, stipulates that companies established in Poland mist issue and report their structured electronic invoices through this system, with the aim of standardizing tax processes and strengthening VAT control.
Since January 1, 2022, KSeF has been available on a voluntary basis, allowing companies to gradually prepare before it becomes mandatory.
Gradual implementation (KSeF)
The entry into force is being carried out in stages:
- February 1, 2026: start of the obligation for large taxpayers, i.e., companies with an annual turnover exceeding PLN 200 million.
- April 1, 2026: extension of the requirement to all other taxpayers established in Poland.
What is the National Electronic Invoicing System – KSeF?
The National Electronic Invoice System (KSeF) is the central platform managed by the Polish Tax Administration for the issuance and receipt of structured invoices.
From 2026:
- All B2B invoices must be sent to KSeF in structured XML format.
- The system will validate the content and assign a unique identifier called KSeF ID.
- Only after validation will the invoice be considered officially issued.
The KSeF portal also acts as:
- Official invoice repository (with 10-year retention).
- Platform for consultation and download in XML or PDF format.
- Notification system using electronic acknowledgements (acceptance, rejection, system unavailability, etc.).
A structured invoice is one issued in XML format in accordance with the official schema and managed exclusively through KSeF.
FA(3) logical structure
On May 8, 2025, the Ministry of Finance published the draft FA(3) schema, which officially replaces the FA(2) shcema as of January 2026.
The FA(3) structure:
- Introduces new mandatory and optional fields.
- Strengthens validation controls.
- Improves the consistency of tac and accounting data.
- Incorporates adjustments derived from public consultation and experience during the voluntary period.
What is the KSeF certificate used for?
The KSeF certificate is one of the methods available for authenticating yourself in the system.
In addition, it is mandatory to mark an invoice with a QR code that allows the issuer's identity to be verified when invoices are issued in special modes: offline24, offline (due to system unavailability), and emergency mode.
Types of KSeF certificates
In the KSeF (Krajowy System e-Faktur) system, there are two types of certificates, each with a different purpose:
- KSeF certificate for authentication
- This is mandatory for issuing invoices in special modes: offline24, offline due to system unavailability, and emergency mode.
- It allows the user to access and operate in the system on behalf of the taxpayer (according to the permissions granted).
- It works as an alternative to other authentication methods, such as qualified electronic signature, qualified electronic seal, or trusted profile.
- KSeF certificate for special modes (offline)
- This is mandatory for issuing invoices in special modes: offline24, offline due to system unavailability, and emergency mode.
- It allows a verification code (QR) to be included on the invoice to confirm the identity of the issuer when the invoice is issued outside the system and subsequently sent to KSeF.
New features in the national electronic invoicing system (KSeF)
1. Offline mode until the end of 2026
Voluntary use of offline mode is permitted until December 31, 2026. This mechanism allows invoices to be issued outside the system in specific situations, with subsequent submission to the KSeF.
The concept of “offline24” is also introduced, which allows the invoice to be sent the next day in certain technical cases.
2. B2C invoicing
Invoices to end consumers (B2C) may be issued through KSeF on an optional basis.
3. Invoice attachments
Attachments may be added to structured invoices, regardless of the sector of activity.
4. Low-value invoices
Taxpayers who issue simplified invoices for low amounts (up to PLN 450 per invoice or PLN 10,000 per month) may continue to use the current format until September 30, 2026.
5. KSeF number in payments
The obligation to include the KSeF number in bank transfers (including payments with a split payment mechanism) will apply to payments made from August 1, 2026. Until that date, no penalties will be imposed in relation to this obligation.
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Benefits of the B2B electronic invoice in Poland
Companies that decide to start using e-invoices on a voluntary basis can benefit from some special measures:
- Reduction of VAT declaration from 60 to 40 days.
- Exemption from the JPK_FA file declaration.
These are some of the advantages that the government expects to see with the mass implementation of the B2B invoice.
- Increase control of the tax system while at the same time limiting irregularities in the VAT settlement.
- Contribute to improving the process through easier and faster access to documents.
- Provide greater security to commercial transactions with a standardized invoice.
- Increase state budget revenues due to the supposed increase in VAT collection.
- Improve the competitiveness of the economy and the entrepreneurial mindset, including entrepreneurship.
- Provide the ability to issue e-Invoices using a structured invoice template, with archiving being provided by the tax authority.
EDICOM’s Compliance Service in Poland
EDICOM offers a complete solution for companies established in Poland. EDICOM’s e-invoicing and VAT compliance solutions enable the automation of all B2B and B2G invoicing and tax document declaration processes. The solution can be fully integrated with any ERP, facilitating the generation and issuance of electronic invoices to the KSeF platform, as well as the electronic invoices issued to the Polish Public administration through the PeF central government platform, in compliance with the technical and legal requisites imposed by the Ministry of Finance.
EDICOM’s is also able to automate the issuance of SAF-T files to declare accounting data. EDICOM’s all-in-one solution will help reduce VAT return times, reduce management costs, and guarantees maximal security and confidentiality.
How the EDICOM solution works
- Data Capture: first, our solution integrates with your ERP or accounting system to capture invoice data.
- File Generation: an XML-structured data file is then generated in compliance with regulations.
- Connectivity: a Web Service call required to send the files to the tax authority is made.
- Integration and Reception: The Polish tax authority issues notifications about the status of invoices. These responses are automatically integrated with the client's ERP or accounting system.
- Archiving: XML files of invoices and their associated statuses are stored in our eIDAS-certified electronic archiving system.
