All About B2B E-Invoicing in Poland
Poland's Mandatory B2B E-Invoicing via KSeF from February 2026, B2G E-Invoicing through PeF Platform, Voluntary B2C E-Invoicing
Last modified on 2025-10-01 in Blog
KSeF schema (B2B), Peppol-UBL (B2G)
PeF (B2G) and KSeF (B2B)
Ministerstwo Finansów
Central Platform Exchange
2019
1 July 2024
10 years
Poland stands out as a nation that recognizes the importance of a robust digital and safety infrastructure for its economic future. Poland is undergoing a significant transformation in its invoicing and tax compliance systems with the introduction of mandatory B2B electronic invoicing. Through its national e-invoicing platform, Krajowy System e-Faktur (KSeF), Poland is joining the forefront of European countries that have embraced digital invoicing.
Starting February 2026, every Polish business must comply with mandatory B2B e-invoicing through KSeF or face automatic invoice rejection and penalties. With the final FA VAT (3) schema now published and testing environments live, businesses have limited time to integrate their systems and avoid compliance disruptions that could impact cash flow and operations.
In 2025, Poland advanced its mandatory B2B e-invoicing system with the release of updated FA(3) invoice schema and KSeF API 2.0 for improved integration. Open API testing and a test version of the KSeF Taxpayer Application are scheduled for late 2025, alongside new secure emission certificates. The rollout will begin with large companies, followed by others, with extended deadlines and a penalty-free transition period through 2026 to support smooth adoption.
Ready to ensure your business meets Poland's new e-invoicing requirements? Contact our experts for a free compliance consultation.
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E-invoicing goes beyond digitizing paper invoices, it creates machine-readable, structured documents that enable automatic processing, seamless accounting system integration, and instant tax authority reporting.
Poland is implementing e-invoicing to tackle VAT fraud through real-time transaction monitoring while accelerating VAT refunds that improve business cash flow. The system reduces manual processing errors, speeds up payment cycles, and ensures legal authenticity through certified electronic signatures under the eIDAS framework.
While large corporations already operate advanced internal solutions, nationwide adoption is gathering momentum as authorities focus on the long-term benefits of transparency and efficiency.
This digital shift also aligns Poland with EU regulations and standards like EN 16931, positioning Polish businesses for seamless cross-border trade in Europe's increasingly connected marketplace.
Poland’s e-invoicing story spans several years of development, marked by multiple legislative and technical updates:
There remains understandable caution regarding government oversight, but the gradual and consultative approach adopted by Polish regulators helps build confidence across the business landscape.
The public sector in Poland already mandates standardized electronic invoicing procedures through the Platformy Elektronicznego Fakturowania (PeF) platform, which complies with EU Directive 2014/55. All public offices must accept electronic invoices ensuring greater efficiency, transparency, and cost savings in public procurement.
Invoices issued to public entities must be digitally signed to guarantee authenticity and include procurement-specific identifiers such as contract and project codes. The system performs automatic validation, rejecting invoices that do not meet legal or technical criteria, thereby safeguarding proper payment processing.
The PeF is the central platform through which B2G e-invoicing is currently conducted. It uses a standardized XML format based on the Peppol network in order to send and receive invoices.
It consists of 2 Peppol Access Points which can be implemented through e-invoicing service providers such as DDD Invoices who send the e-invoice through KSeF and deliver the invoice to the client.
Beginning February 1, 2026, every domestic B2B invoice in Poland must be issued and submitted through KSeF using the FA(3) XML format. Unlike in many other EU countries, Poland has obtained a waiver allowing it to mandate e-invoicing without requiring the recipient’s acceptance, simplifying compliance and adoption.
Each invoice undergoes real-time compliance checks, receives a unique KSeF identifier and timestamp, and is archived securely for a decade. This ensures traceability and audit readiness while reducing risks associated with tax evasion.
Firms are expected to integrate their ERP or accounting software with the KSeF API, allowing automatic generation, submission, and retrieval of invoices, reducing manual errors and improving operational workflows.
There is a penalty grace period: no fines for invoice mistakes until the end of 2026. The aim is to make tax reporting faster and more modern, like in other EU countries such as Italy, where B2B e-invoicing has been required since 2019.
By prioritizing the advantages of digital invoicing, such as compliance, operational streamlining, and improved security, Poland is laying the foundation for a safer, more connected, and competitive economy.
You do not need to know anything about e-invoicing standards or real-time reporting.
At present, B2C e-invoicing remains voluntary in Poland. Businesses may choose to issue consumer invoices electronically through KSeF’s platform, using the same FA(3) XML standards. The system is designed with future expansions in mind and supports consumer access to electronically issued invoices, adding transparency and convenience.
However, fiscalization requirements for B2C transactions are already mandatory in many sectors. Polish businesses must use certified cash registers that can transmit real-time sales data to tax authorities, ensuring immediate reporting of consumer transactions. This fiscalization system operates alongside the voluntary e-invoicing framework, creating a dual approach to B2C tax compliance.
The Polish government is likely to consider extending the mandate to B2C invoicing as part of ongoing digital fiscal reforms, following the lead of countries like Italy, Slovenia and Montenegro.
Foreign companies with a Polish VAT registration are obligated to issue invoices through the KSeF platform using FA(3) format. Those without Polish VAT numbers are exempt but must comply with local regulations by allowing their Polish customers to produce “self-invoices” in KSeF.
Cross-border invoices must meet both Polish invoicing requirements and the originating country’s legislation, recognizing the complexities of the EU’s digital VAT landscape. Invoices submitted late or without required data face rejection and penalties.
Poland does not use the SAF-T format commonly adopted by other EU countries. Instead, it relies on the real-time data submitted via KSeF for comprehensive VAT monitoring and reporting.
Similarly to other countries such as Serbia and Italy, Poland has created a national electronic invoicing system called Krajowy System e-Faktur (KSeF). KSeF is a central platform through which taxable persons established in Poland can comply with obligatory e-invoicing.
Standardized and structured e-invoicing has many benefits over the previous system of invoicing in Poland such as VAT return times decreasing to 40 days instead of 60. Users can download invoices in XML or PDF format via the KSeF national platform although they are technically not treated as electronic invoices in Poland anymore under the new legislation.
On June 30, 2025, the Ministry of Finance published the KSeF 2.0 API documentation, following the final FA_VAT (3) schema release on June 25, 2025. The new API documentation enables integrators to prepare for testing in the KSeF 2.0 TEST environment, available from September 30, 2025. Released materials include API specifications in OpenAPI 3.0.4 format, interactive documentation, and the KSeF 2.0 integrator guide.
When an invoice is issued, KSeF validates it against technical and legal criteria, assigns a unique identifier and timestamp, and archives it securely under eIDAS-compliant protocols. Authentication is supported through qualified electronic certificates or secure tokens.
KSeF supports four offline modes: Offline24, planned maintenance, announced emergency mode, and full system failure. Invoices issued in offline modes (except full system failure) distributed outside KSeF must include two QR codes: 'offline' and 'certyfikat'.
Two types of QR codes are used:
KSeF certificates will replace tokens as the authentication method from January 1, 2027. Applications open November 1, 2025, for taxpayers and authorized representatives. Certificates are valid for two years and required to generate 'certyfikat' QR codes.
Entities making payments for e-invoices (online and offline) must provide a KSeF number or collective ID on bank transfers. The Ministry of Finance has outlined the structure and generation process for collective IDs.
Non-compliant invoices are automatically rejected with detailed error messages, requiring correction and resubmission to ensure strict adherence to invoicing standards.
Choosing the right e-invoicing provider is key to easily meeting Poland's new rules. Providers need to support smooth integration with KSeF, convert invoices into the required FA(3) XML format, submit them automatically, and handle errors efficiently.
DDD Invoices is Poland's proven KSeF specialist, delivering direct system connectivity that fully automates your invoice lifecycle, from creation through transmission to secure archiving. We transform complex compliance requirements into streamlined operations that protect your business and enhance efficiency.
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Mandatory B2B e-invoicing through KSeF starts on February 1, 2026, for large companies. From April 1, 2026, all VAT-registered businesses in Poland must use it.
KSeF makes invoicing easier by checking invoices in real-time, giving each invoice a unique ID, and storing them safely. This helps prevent fraud and speeds up VAT refunds.
Yes, B2C e-invoicing is currently voluntary in Poland. Businesses can choose to issue electronic invoices to consumers through the KSeF platform using the same FA(3) XML standards.
Written by the Compliance team
Reviewed by Denis V. P.
DDD Invoices is an enterprise-grade platform delivering a powerful infrastructure for creating, sending, receiving and storing electronic documents. DDD Invoices enables software providers like ERPs, SaaS, eCommerce, POS systems, accounting & invoicing softwares, billing services and others, to easily adhere to global invoicing compliance requirements and shorten their time-to-market.