Poland Advances KSeF E-Invoicing Rollout as 2026 Consultation Phase Goes Live

On 9 June 2026, the Polish Ministry of Finance launched a new consultation round covering enhancements to the National e-Invoicing System (KSeF), including updates to business event models, invoice process management, and technical improvements to the KSeF 2.0 API. One of the Ministry of Finance’s proposals is to retain tokens as one of the methods for logging into KSeF.

The consultation forms part of Poland’s continuing preparations for mandatory B2B e-invoicing and accompanies further technical specifications and legislative refinements ahead of full implementation.

This latest consultation follows the Ministry’s earlier announcements in April 2026, which confirmed the final implementation timetable for mandatory KSeF e-invoicing, published additional Frequently Asked Questions (FAQs), and introduced a transitional penalty-free period extending throughout 2026.

KSeF Implementation Timeline

Poland’s phased rollout of mandatory e-invoicing will proceed as follows:

1 February 2026

Mandatory KSeF e-invoicing for large taxpayers with annual turnover exceeding PLN 200 million (based on 2024 revenues).

1 April 2026

Mandatory KSeF e-invoicing for all remaining taxpayers registered for Polish VAT.

1 January 2027

Implementation of the final phase covering:

• Micro-businesses issuing invoices below PLN 450;
• Businesses with monthly sales below PLN 10,000;
• Mandatory reporting of invoices issued through cash registers;
• Mandatory inclusion of KSeF invoice numbers in business-to-business payment references;
• Commencement of the penalty regime for non-compliance.

Which Transactions Must Be Reported Through KSeF?

Although KSeF represents a broad clearance-based invoicing regime, the obligation does not apply to every transaction.

Transactions Within Scope

Domestic B2B Transactions

The core mandate covers supplies between businesses that are both registered for VAT in Poland. Invoices for these transactions must be issued through KSeF.

Business-to-Government (B2G) Transactions

Invoices issued to Polish public authorities and government entities are also required to follow the KSeF process.

Cross-Border Outbound Transactions

Invoices relating to exports and intra-EU supplies made by Polish VAT-registered businesses must be submitted to KSeF, even where the transaction benefits from a 0% VAT rate.

Because foreign customers do not have access to KSeF, suppliers must separately provide a readable copy of the invoice, typically in PDF format, containing the KSeF reference number and verification code.

Transactions Outside Mandatory KSeF

Domestic B2C Transactions

Invoices issued to private consumers are not subject to mandatory KSeF clearance. Traditional invoicing methods and fiscal receipts remain available, although voluntary KSeF usage is permitted.

Inbound Foreign Supplier Invoices

Invoices received from foreign suppliers that are not registered for VAT in Poland remain outside KSeF and continue to be processed through standard accounting and VAT reporting procedures.

Specific Exemptions

Additional exclusions and transitional carve-outs apply to:

• Certain small taxpayers meeting specific turnover thresholds;
• Cases of digital exclusion;
• Selected self-billing arrangements;
• Transactions reported under OSS and IOSS schemes;
• Pro-forma invoices;
• Transport tickets and similar documents treated as invoices.

Who Must Comply?

Polish Established Businesses

Companies established in Poland are fully within scope, regardless of whether they are VAT-taxable or VAT-exempt entities.

Foreign Businesses with a Fixed Establishment

Non-Polish companies operating through a fixed establishment in Poland that participates in taxable transactions are generally required to comply with KSeF obligations.

Foreign VAT Registrations Without Physical Presence

Businesses that are merely VAT-registered in Poland but lack personnel, infrastructure, or a fixed establishment may remain outside the mandatory KSeF obligation. This reflects the Polish government’s intention to reduce administrative burdens for certain non-resident taxpayers.

Obligations for Buyers

Polish VAT-registered recipients must ensure they are technically capable of receiving and processing invoices through KSeF. Acceptance of KSeF invoices is mandatory under Polish law.

Invoice Format and Technical Requirements

FA(3) Structured XML Format

All invoices submitted through KSeF must comply with the FA(3) XML schema, Poland’s latest structured e-invoice format.

The schema aligns closely with European e-invoicing standards, including EN 16931 and Peppol BIS requirements.

Mandatory Data Elements

Structured invoices must contain all legally required invoice information, including:

• Supplier and customer identification data;
• Invoice dates and numbering;
• Detailed line-item information;
• VAT rates and VAT amounts;
• Invoice totals;
• Currency information;
• Reverse-charge and other statutory indicators where applicable.

Unique KSeF Identification

Upon successful validation, KSeF assigns a unique identification number to each invoice and enables generation of a corresponding QR code for verification purposes.

No Electronic Signature Requirement

Invoices do not require a qualified electronic signature. Legal authenticity and integrity are established through submission, validation, and timestamping within KSeF.

Submission and Clearance Process

System Access

Businesses may connect directly through APIs integrated into ERP or billing systems, or use government-provided web portals and mobile solutions.

Secure taxpayer authentication is required.

Clearance Validation

Invoices undergo automatic validation checks upon submission. Only validated invoices are accepted, timestamped, and legally recognized as issued.

Invoices that fail validation are considered not issued and must be corrected and resubmitted.

Customer Receipt

For domestic recipients, legal receipt occurs when the invoice becomes available in KSeF.

For foreign customers, suppliers must provide the invoice separately together with the KSeF reference information.

Timing Requirements

Invoices should be submitted to KSeF at the time of issuance or as close as possible to the taxable transaction.

Contingency Procedures

Where technical issues prevent real-time submission, invoices may be issued offline and uploaded no later than the following business day. Similar contingency procedures apply during official KSeF outages.

Penalties and Enforcement

Transitional Relief During 2026

The Ministry of Finance has confirmed that no monetary penalties will apply during the initial implementation period in 2026, providing businesses with additional time to adapt systems and processes.

Penalties from 1 January 2027

From January 2027, administrative sanctions may apply where taxpayers fail to comply with mandatory KSeF obligations.

Potential penalties may reach:

• Up to 100% of the VAT amount shown on the invoice; or
• Where no VAT is charged, approximately 18.7% of the gross invoice value.

Additional penalties may arise where offline invoices are not uploaded within the prescribed deadlines.

Non-compliant invoices may also create VAT deduction risks and commercial disputes with customers.

Archiving and Record Retention

Centralized Storage

All invoices submitted through KSeF will be stored centrally by the Polish tax administration for ten years.

This retention period exceeds Poland’s standard VAT limitation period and provides long-term access to invoice records.

Reduced Administrative Burden

Because KSeF serves as the official invoice repository, taxpayers are generally relieved from maintaining separate tax archives for KSeF invoices.

Continued Internal Record Keeping

Although no longer legally required for tax archiving purposes, businesses are strongly advised to maintain internal copies of invoices for operational continuity, reporting, analytics, and disaster recovery purposes.

Looking Ahead

With the June 2026 consultation phase now underway, Poland continues to refine one of Europe’s most ambitious clearance-based e-invoicing systems. Businesses should use the remaining implementation window to complete ERP integrations, validate invoice processes, test KSeF connectivity, and assess the impact on domestic and cross-border transactions.

Particular attention should be paid by foreign businesses operating in Poland, as the final scope of obligations for non-resident VAT registrations and fixed establishments remains a key area of practical compliance analysis.

How Can KGT Support You?

KGT has created an SAP-integrated SAF-T add-on solution for Poland, featuring outbound and inbound functionalities to meet tax reporting requirements. This add-on includes a data extractor and a cockpit for generating periodic e-invoicing files in the legal format and controls before submission. When SAP DRC launched the Polish e-invoicing solution as part of its e-document offerings, KGT emerged as a leading consultancy firm for SAP DRC and tax services. Recognized as an SAP DRC partner for Polish e-invoicing services, KGT is one of SAP's recommended implementation partners for this solution. We provide comprehensive support, including installation, configuration, customization, and training, to help you maximize the long-term value of your SAP DRC investment.

KGT is an SAP partner for PE services and an SAP Build partner, and to become an SAP partner, strict due diligence requirements must be met, including having certified SAP consultants. You can find us at: https://partnerfinder.sap.com/profile/0001925409