Poland is the fourth country in the European Union to introduce e-Invoice – API specification

The Polish Ministry of Finance on 20 October 2021 issued a specification for the National e-Invoicing System (NeIS), providing tips for software developers wishing to integrate their programs with NeIS (API). This specification is not a source of law, but is only a set of guidelines for developers. The NeIS test environment website ( does not contain a graphical user interface for uploading or downloading invoices. It contains material intended for IT departments working on integration with NeIS. This address is also used by the published API. The logical structures used by the API, the OpenApi (formerly Swagger) documentation and editor, and the test environment public key have been made available. For the time being, no descriptive interface specification has been published, as was the case for e-Declaration or the Single Control File. It has been indicated that the test version will use self-generated signatures and seals for authorisation in NeIS, the test version does not offer authorisation via the Trusted Profile and token at this point. Invoices will be submitted using the API provided in batch or interactive mode. An Official Delivery Certificate will be available with a list of invoices sent in a batch packet or during an interactive session. The provided service will verify the correctness of the sent invoices with the working version of the XSD schema. The API introduces permissions that can be assigned to a system user. A privilege management facility is provided that will allow to view, grant and revoke privileges. The types of roles available in the process are also indicated. It is worth noting that the message states that it is planned to make the use of e-Invoice mandatory for entrepreneurs in Poland from 2023.


Central Register of Invoices and Central Database of Invoices in Poland – Polish e-revolution from 2022

What is the Central Register of Invoices and the National e-Invoice System

Poland as the fourth country of the EU countries decided to introduce the Central Invoice Register as another mechanism to prevent fraud against VAT. The Central Invoice Register is also known as the Central Invoice Database or the National e-Invoice System. It is a system that brings together all the invoices issued by entrepreneurs. It was established in order to tighten the tax system and prevent tax fraud. The Polish National e-Invoice System began its operation on 1 January 2022 under the Act of 29 October 2021 amending the Act on Value-added Tax and certain other acts (Journal of Laws of 2021, item 2076). The National e-Invoice System (NeIS) allows structured invoices to be issued and made available. On the basis of Art. 106nb of the Act on Value-added Tax of 11 March 2004, NeIS can be used by taxpayers, entities indicated by the taxpayer (e.g. an accounting office), enforcement bodies specified in the Act on Enforcement Proceedings in Administration of 17 June 1966 and court bailiffs performing enforcement actions within the meaning of the provisions of the Code of Civil Procedure in cases indicated in Art.106c of the VAT Act, natural persons indicated by such entities, natural persons indicated in the notice on granting or withdrawing the right to use the National e-Invoice System to whom the taxpayer or entities referred to in Art. 106c of the VAT Act have granted the right to use this system, entities other than listed, indicated by natural persons using the National System for e-Invoices, if the right to indicate another entity results from the rights granted to such natural persons.

Tasks and aims of the Central Invoice Register