Implementing new technologies in a company is often like trying to open a door for which we don’t yet have a key. The National e-Invoice System (KSeF) is precisely such a digital house that every business owner will soon have to enter. The question is: what key will you use? Will it be the traditional method with a touch of bureaucracy (ZAW-FA), or a modern, digital master key (qualified digital certificate)?
As experts at podpisano.pl a look at the two main ways your company can access the system. Understanding this difference is crucial, especially if you’re wondering how to integrate KSeF with a sales platform or accounting system.
KSeF (National e-Invoice System) is a nationwide IT platform used for issuing and receiving structured invoices. To ensure the system knows that “you are you” (or more precisely, that your company is your company), you must authenticate yourself. Without this, you will not be able to send or receive any documents.
For self-employed individuals (sole proprietors), it’s simple—they can log in using a Trusted Profile or a qualified digital signature. Things get more complicated when it comes to corporations and other entities that aren’t individuals. That’s where our two heroes come in.
The ZAW-FA notification is a form used to designate a specific individual as the person authorized to manage the company’s permissions in KSeF.
When is it used? Mainly when there is no one in the company who can log in automatically (e.g., the company does not have a qualified digital seal, and its representation is specified in the National Court Register, which the KSEF IT system cannot verify on its own).
How does this work in practice? The person(s) authorized to represent the company (as per the entry in the National Court Register) sign the completed ZAW-FA form, in which they designate a specific individual (with a PESEL number) as the company’s account administrator. This document is often submitted in paper form or via ePUAP, but only after the company’s account has been established with the Tax Office. The official enters the data into the system and… voila. The designated person logs in using their personal Trusted Profile or digital signature, acting on behalf of the company.
This is where we enter the world of QSeal (Qualified Electronic Seal ). It is the digital equivalent of a company stamp, but with the same legal force and level of security as a handwritten signature (in terms of data integrity and authenticity of origin).
The stamp contains the company's information (e.g., tax ID number, name, business registration number), not John Smith's personal information.
Why is this a “game changer”? The stamp enables full automation. When business owners ask, whether invoices can be automatically generated in KSeF without an employee having to log in manually, the answer is: yes, if you have a seal.
If you run a small business, issue five invoices a month, and are wondering what the benefits of using KSeF are for small businesses, and your budget is tight—ZAW-FA might be a good starting point.
However, if your company is a dynamic entity that issues hundreds of documents, and your search query is: what are the technical requirements for using KSeF on a large scale or how to secure data sent to KSeF during bulk transmission—a qualified digital seal is the only right choice. It is the standard in professional business transactions.
At podpisano.pl a #paperless approach. An electronic seal isn’t just a technical requirement—it’s a tool that builds credibility and streamlines processes. Also, keep in mind that the most common errors when sending invoices via KSeF often stem from human error—automation using an electronic seal eliminates this risk factor.
No matter which path you choose, remember that KSeF is a revolution that requires preparation. Don’t leave it until the last minute!
If you want to learn more about how a qualified electronic signature can improve not only KSeF, but your entire company, visit podpisano.pl.
For more information on KSeF procedures, visit the official website ksef.podatki.gov.pl and in our knowledge base.
This article was prepared based on the KSeF 2.0 Handbook (Ministry of Finance, September 2025) and information from the website ksef.podatki.gov.pl.
