Sovos’ team of regulatory tax experts answer some of the most frequently asked questions about KSEF 2.0, an upcoming update to Poland’s national electronic invoicing system.
1. What are the main changes in KSeF 2.0?
KSeF 2.0 introduces several important features not available in the 1.0 system in use during the voluntary period. The most significant changes include:
- Optional B2C e-invoicing
- The permanent Offline24 Mode allowing businesses to issue invoices outside the system and submit them to KSeF by the next working day
- Mandatory QR code for invoices issued in offline modes
- mandatory use of the updated FA(3) logical structure format
- Postponement of deadlines for certain KSeF-related obligations
2. What is the implementation timeline for KSeF 2.0?
The KSeF 2.0 implementation begins with open testing from September 30, 2025, followed by KSeF certificates availability on November 1, 2025. As confirmed by the KSeF 2.0 Act, mandatory structured e-invoicing starts February 1, 2026 for taxpayers with sales exceeding 200 million PLN in 2024, and April 1, 2026 for all other taxpayers.
An exemption allows taxpayers with monthly sales below 10,000 PLN to continue issuing paper or electronic invoices until December 31, 2026.
3. Which entities are obligated to use KSeF?
According to the Polish legislation, the mandatory e-invoicing obligation through KSeF will apply to:
- Taxpayers with a registered office in Poland
- Taxpayers with a permanent place of business in Poland that is involved in the delivery of goods or provision of services for which the invoice is issued
4. Does sole VAT registration in Poland mean a company is subject to KSeF?
Polish legislation states that the taxpayer must have either a registered office or a permanent establishment in Poland that participates in the transaction to fall under mandatory KSeF. VAT registration alone does not trigger the obligation.
5. What documents are included in KSeF and what are excluded?
Not all document types fall within the scope of the KSeF system. The system supports VAT invoices, corrective invoices, self-billing invoices, and VAT RR invoices (optional from April 2026). However, several documents are excluded from KSeF, including internal invoices, pro forma invoices, and traditional debit/credit notes.
6. Are cross-border transactions included in the KSeF mandate?
Yes, Polish businesses must submit e-invoices to KSeF for sales to foreign customers. After submission, the Polish supplier must provide the invoice to the foreign customer in an agreed format, including a QR code for KSeF access. This applies to all cross-border sales by Polish taxpayers under KSeF.
7. How can taxpayers access invoices from the KSeF system?
Taxpayers have multiple options to receive their e-invoices from the KSeF platform:
- Direct integration with the tax authority by connecting to the KSeF’s API
- Through a third-party service provider who can retrieve e-invoices on their behalf
- Manually downloading e-invoices via the KSeF portal
8. How does KSeF 2.0 handle B2C transactions compared to KSeF 1.0?
Unlike KSeF 1.0, which did not support B2C e-invoicing, KSeF 2.0 allows voluntary B2C e-invoicing. Consumers must still request an invoice before one can be issued, but the issuer decides whether to fulfill this request via KSeF or through traditional methods without requiring consumer consent.
9. How will consumers access their invoices in KSeF?
The KSeF 2.0 legislation establishes an “anonymous access” mechanism for consumers. When sellers issue e-invoices to consumers through KSeF, they must provide one of the following:
- A verification code for the invoice in the system and data that enables identification of the invoice
- A QR code that enables access to the e-invoice in KSeF
Consumers can use these methods to access their invoices without the need to log into the system.
10. How do credit and debit notes work in the KSeF system?
Traditional credit and debit notes as separate document types (commonly used in many countries) won’t be part of the KSeF system. Instead, all corrections must be made through a “corrective invoice” document type that KSeF supports. Additionally, correction notes issued by buyers in Poland will also remain outside KSeF’s scope.
11. What certificates or access credentials are needed to issue in KSeF 2.0?
Authentication can be done via:
- Electronic identification linked to the national node
- Qualified electronic signature or seal
- KSeF certificate obtained after initial authentication by one of the first three methods.
The Trusted Profile method will be eliminated from 1 April 2026. KSeF Certificates will be available for download from November 1, 2025 via the Certificates and Authorizations Module (MCU), which will be made available in the KSeF domain.
12. What offline modes are available in KSeF 2.0?
KSeF 2.0 offers four offline modes. Offline24 mode is designed for issues on the taxpayer’s side, such as connectivity problems and internet outages. Offline mode is for planned system maintenance periods when KSeF is temporarily unavailable. Failure mode is for unplanned system failures that are officially announced in the bulletin of the Ministry of Finance. Total failure mode is for extraordinary situations like threats to the country’s infrastructure, announced through media channels.
13. What is the Offline24 mode in KSeF 2.0 and how does it work?
Offline24 mode is a solution created to address concerns about potential delays in invoice submission due to issues on the taxpayer’s side. It allows businesses to issue structured invoices outside the system, and to submit them to KSeF no later than the next business day following the FA(3) format.
14. How do recipients receive invoices issued in Offline24 mode in KSeF 2.0?
Domestic business recipients with a NIP receive invoices exclusively through the KSeF system after their submission and clearance. Other recipients (consumers, foreign entities, or entities without a NIP) receive invoices in a manner agreed with the buyer outside of KSeF, with one or two QR codes.
15. What are the QR code requirements for invoices in KSeF 2.0?
When an invoice is sent to the recipient outside KSeF, it must include one or two QR codes. There are two types of QR codes: one for accessing the invoice and another for ensuring integrity and authenticity. If the invoice is provided to the recipient after KSeF clearance, only the access QR code is required. When providing the invoice to the recipient before KSeF clearance, the two QR codes are needed.
16. Is a QR code required on non-domestic invoices?
Access QR codes are mandatory on all invoices exchanged outside the KSeF system, including cross-border transactions. Polish companies must first submit the e-invoice to KSeF, then provide it to foreign partners in any agreed format along with a QR code. This allows foreign recipients to verify the invoice’s authenticity and access it in the Polish tax authority’s system when needed.
17. What invoice format will be used in KSeF 2.0?
From February 1, 2026, KSeF 2.0 will exclusively use the FA(3) logical structure for all structured invoices. The FA(3) schema includes enhanced features like support for attachments, inclusion of new fields and other updates to code formats, schema variants, and data types.
18. What are invoice attachments in KSeF 2.0 and what can they contain?
Invoice attachments in KSeF 2.0 are an integral part of structured invoices designed specifically for entities who need to include complex detailed data in their invoices. Attachments can only contain mandatory invoice elements specified in the Polish VAT Act or closely related data, while including marketing information and advertising content is prohibited.
19. How can businesses include attachments with invoices in KSeF 2.0?
To include attachments with invoices in KSeF 2.0, businesses must submit a notification via the e-Tax Office to the National Tax Administration before using this feature. The attachment functionality, available from January 1, 2026, is valid for 2 years after approval and requires renewal to continue.
20. Will there be a transitional period when penalties won’t apply for KSeF-related violations?
Yes. From February 1, 2026, to December 31, 2026, financial penalties for KSeF-related violations will not be enforced. This transitional period allows businesses time to adapt without facing fines.
Want to learn more about KSEF 2.0 and Poland’s e-invoicing requirements?
Sovos has created a number of resources to help businesses prepare for Poland’s KSEF 2.0 e-invoicing requirements:
- Poland e-invoicing tax rules – the main webpage to stay up to date with current and upcoming e-invoicing regulations in Poland
- Preparing for KSEF 2.0 – a blog to help businesses understand the impact of the upcoming changes
- KSEF timeline – a comprehensive timeline of Poland’s e-invoicing mandate, updated with the latest announcements from the tax authority