KSeF for sole proprietorships (JDG)
KSeF, the National e-Invoicing System, is a state system for issuing, receiving and storing structured invoices.
An invoice will no longer be merely a PDF file sent by e-mail. An invoice issued in KSeF goes to a central system and receives a special identification number.
From when does KSeF apply to a sole proprietorship?
From 1 February 2026 business owners have to reckon with the fact that some purchase invoices will be available in KSeF, especially from larger counterparties.
From 1 April 2026 the obligation to issue invoices in KSeF covers most of the remaining taxpayers, including sole proprietorships.
For the smallest firms a temporary exception has been provided – if the value of sales documented by invoices in a given month does not exceed 10 000 zł gross, they may issue invoices outside KSeF until the end of 2026. Once the limit is exceeded, the obligation to issue invoices in KSeF arises as of the invoice that exceeded that limit.
How does a sole proprietorship gain access to KSeF? The owner of a sole proprietorship can log into the system as a natural person, using the Trusted Profile or a qualified electronic signature.
The business owner should check whether they can log into the system and whether their accounting office has the appropriate rights to handle the documents.
Until now many business owners sent invoices to their accounting office by e-mail, through a client panel, or handed them over on paper.
In KSeF this flow changes.
That is why it is worth settling in advance:
• who issues the sales invoices,
• who receives the cost invoices,
• whether the accounting office is to have access to KSeF,
• whether the invoicing software supports KSeF.
Check whether you have an active Trusted Profile or a qualified signature. Log into KSeF or into the software you are going to use. Agree with your accounting office who will download the cost invoices and what rights need to be granted.
Most importantly: do not treat the PDF as the only source of the document.
In KSeF the invoice lives in the system, not merely as an attachment to an e-mail.
Who is responsible for access to the invoices? It is the business owner who is responsible for their own company, for issuing invoices and for granting the right accesses. Without this, the accounting office may have no way of downloading the documents from KSeF. The accountants can help, but the business owner has to give them access to the invoices.
KSeF need not be a problem if you prepare in advance.
It is worth checking your access, your invoicing software and the way documents are passed to the accounting office right now. That way you will avoid stress, arrears and problems with settling invoices.
If you run a sole proprietorship and do not know where to start preparing for KSeF – get in touch with us.
Fengo Sp. z o.o. | Accounting Office | Cieszyn
www.fengo.pl | biuro@fengo.pl
The article above is for information and educational purposes only. It does not constitute tax advice within the meaning of the Act of 5 July 1996 on tax advisory services. In individual cases we recommend consulting a tax adviser or the competent tax authority.
