KSeF: National System of e-Invoices in Poland

Prepare your company for the National System of e-Invoices (KSeF)

Learn how you can send and receive electronic documents to/from KSeF by using our EDI platform

What is the National System of e-Invoices

The National System of e-Invoices (KSeF) is a data exchange system for issuing, receiving, and storing structured invoices. It is also used for marking invoices with an identifying number, as well as checking whether one’s invoices are compliant with a specific pattern.

On January 1, 2022, this system will be introduced in Poland as a voluntary solution. The Polish Ministry of Finance wants KSeF to become an obligatory solution in 2023 (after obtaining the derogation decision from the European Commission) and electronic invoicing to become mandatory for all entities in the same year.

Therefore, Poland is now becoming yet another country that belongs to the European Union (after Spain, Portugal, and Italy), which has decided to change the model of electronic invoice processing from the post-audit model to the clearance model.

The Timeline

National System of e-Invoices in Poland

Prepare your company for the National System of e-Invoices (KSeF)

What is a structured invoice

As described in the Act on amending the Act on tax on goods and services (and several other acts) adopted by the Sejm of the Republic of Poland:

"A structured invoice is issued and received via the National System of e-Invoices using an interface software, it has an electronic form and is created in accordance with a provided template…”

A structured invoice is to be presented in the XML format according to the logical structure of e-Invoices (FA_VAT). Therefore, it is the third type of invoice next to the paper and electronic invoices. It is issued by taxpayers using the KSeF system and marked with a number identifying this invoice in the system.

Structured invoices will be issued according to a template based on the logical structure presented by the Ministry of Finance.

What is a structured invoice?

How is KSEF supposed to work in Poland?

Access to the National System of e-Invoices may be obtained by a taxpayer, an authorized person, an authorized entity, or one of the entities referred to in Article 106c of the Act, provided they are allowed to issue (or access) structured invoices.

The legislator is to provide the possibility of issuing a structured invoice directly in the system (via a web interface) or via the taxpayer's financial and accounting system in accordance with the published template.

When invoices are issued in the taxpayer's financial and accounting system, the documents should be delivered to KSEF via a defined connection, e.g., via EDI to KSeF API.

How is KSEF supposed to work?

Registering invoices in KSeF via Comarch EDI

Being an operator of electronic document exchange (including e-invoices), Comarch constantly monitors legislative changes in Polish law.

We are very much involved in the KSeF pilot project. Our specialists are present at meetings during which the technical details of the system, the specification of a structured invoice, and API documentation are discussed.

The API interface is to enable the integration of Comarch EDI (used by thousands of customers in Poland and abroad) with the National System of e-Invoices.

This means that it will be possible for all users of our platform to send and receive e-invoices to/from KSeF. Comarch EDI will also ensure full compliance with the latest legal regulations and transparency of the flow of all invoices (and their statuses).

Learn more about Comarch EDI

What does the integration of Comarch EDI with KSeF look like?

What does the integration of Comarch EDI with KSeF look like


After the official launch of the National System of e-Invoices in Poland, Comarch EDI users will be able to choose one of two models by which our solution will be connected to the government platform. The first one involves the exchange of e-invoices along with basic validation (making sure that invoices are fully compliant with the KSEF requirements). The second model includes the so-called business validation required by the contractor. You can find detailed diagrams of both models below.

A Scheme of the General Model

A Scheme for Sending an Invoice to KSEF after Validation of the "Pre-invoice"

Global e-invoicing experience

As a global supplier of systems and services for exchanging electronic documents between business partners, Comarch has extensive experience in optimizing the Accounts Payable (AP) and Accounts Receivable (AR) processes.

For years, we’ve been providing support to companies operating both in countries where e-invoicing has already become obligatory (such as France, Spain, Germany, Turkey, and Italy) and places where such an obligation is to be introduced (e.g., in Poland, where, according to the announcement of the Polish Ministry of Finance, the e-invoicing mechanism will be based on the Italian solution).

We’re constantly monitoring changes made to e-invoicing policies worldwide, modifying our solutions and services to be fully compliant with the latest regulations at all times.

Global e-invoicing experience

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