The deadline for implementing the National e-Invoice System (KSEF) is rapidly approaching. The system will be electronic, meaning it should simplify and expedite settlements between contractors. It also seems that electronic means automated, meaning it doesn't require active human involvement. Everything will be handled within the system. However, when issuing structured invoices, the human element is crucial. For the system to issue and send an invoice, someone (a human) must enter the most important data. This raises the question: who will enter this data, meaning who will have access to the KSEF?
There is no single answer to this question. It all depends on who the taxpayer is.
KSeF in JDG
If a sole proprietor issues an invoice, they log into the system, where they have full authorization. They can receive and issue invoices. Such a sole proprietor logs in using a trusted profile, mObywatel, or online banking.
KSeF in the company
However, in the case of a company, a person must be designated to authorize invoices. This authorization is granted using the ZAW-FA form. The form can be submitted electronically or on paper. This person will act on the company's behalf in the system. Alternatively, the company can purchase an electronic seal with a Tax Identification Number (NIP) to be used for logging in. In this case, it is not necessary to submit the ZAW-FA form.
Once a business or company logs into KSeF, they can use their existing authorizations. Users can be granted authorization to issue and receive invoices, manage authorizations, and self-bille. Taxpayers can also grant authorization to issue and receive invoices for other users.
KSeF and the accounting office
If I have a contract with an accounting office, will they handle everything for me?
The answer is simple. If you want the accounting firm to have access to invoices or be able to issue invoices, you must grant the appropriate permissions. They won't have access automatically. All permissions must be granted regardless of the existence of a contract. You can designate the accounting firm or a specific accountant as the authorized person. If you authorize the accounting firm, then access to invoices will be granted only to those individuals who have been granted permissions by the accounting firm. You can also grant permissions to a specific accountant. If the scope of permissions includes permission management, they can grant access to other individuals as well.
Regardless of this, companies that do not have an electronic seal may grant authorizations on the ZAW-FA form.
What to remember
If we want someone else (an accountant or accounting firm) to manage KSeF, we need to grant appropriate permissions. Sharing our credentials, such as the login and password for a trusted profile or providing access to mObywatel (mCitizen), isn't the best idea (not to mention allowing logins through our banking system). Furthermore, we need to know who has access to our invoices. If we change accounting (regardless of whether we have an accounting department or use an external service), we should remember to revoke access from anyone we no longer work with.
This article is for informational purposes only and does not constitute legal advice.
The law is current as of November 10, 2025.
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