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KSeF - How to Use It. A Guide for Entrepreneurs
The National e-Invoice System (KSeF)—a central platform managed by the Ministry of Finance for issuing, sending, receiving, and storing structured invoices—will become mandatory at the beginning of 2026. Below, we present all the most important information about KSeF, including the required implementation deadlines for the new solution, as well as essential tips to help get started with the tool for both sole proprietorships and SMEs.
How long has KSeF been in your company?
Although the national e-invoicing system is scheduled to go into effect in early 2026, it is being introduced in several stages, allowing many businesses to implement the rules at a later date. Therefore, it's worth confirming from the outset when your company is required to adopt the KSeF system.
The first phase, starting February 1, 2026, applies to the largest companies with an annual turnover exceeding PLN 200 million. Other VAT-paying companies are required to adopt the KSeF system from April 1, 2026.
What about micro-enterprises whose monthly revenue does not exceed PLN 10,000? Such entities are required to implement the KSeF only on January 1, 2027.
Would you like to talk about an offer for your company?
What way of using KSeF will be best for us?
Now that we know when KSeF will be in effect at our company, it's time to decide how to use the new solution. Businesses have complete freedom here, but this should be based on the scale of their business, its specific nature, and, above all, the number of invoices generated and received.
For small companies with a moderate scale of operations, free tools will be sufficient to fully cover the need to implement and use KSeF next year. The Ministry of Finance, with the aim to make life easier for entrepreneurs, has developed the e-microcompany application.
For large companies that generate and process hundreds of invoices daily, a free solution may not be entirely sufficient. It is worth considering investing in a commercial program that is designed to handle multiple processes simultaneously. This software is integrated with KSeF 2.0 and provides updates as new rules or changes to regulations emerge.
National e-Invoice System - how to get access?
Once you've decided how to use KSeF, it's time to gain full access. This is a very easy step, but it varies depending on your company's legal form.
In the case of sole proprietorships (JDG), access is possible at any time by logging in via a trusted profile. Alternatively, entrepreneurs can use their qualified signature to gain full access to KSeF. Until the mandatory use of KSeF becomes mandatory, entrepreneurs can test the system in a demo version, ensuring that the new solution holds no secrets on the official launch day.
For companies, the access process requires the submission of an additional form. The ZAW-FA form must be submitted to the tax office, which allows access to the e-fakt system. It's worth noting that this solution is intended for entities other than natural persons and those without a qualified stamp.
How to authenticate a company in KSeF and generate a certificate?
Full implementation of the National e-Invoice System requires businesses to authenticate their companies and generate a dedicated certificate confirming their participation in the system. This is very simple and can be done immediately after gaining access to the National e-Invoice System. The best way will be to generate it in the Ministry of Finance application. Alternatively, a company can generate an access key using a qualified signature, electronic seal, or trusted profile.
Once full access to the platform has been granted, it's time to assign permissions. In sole proprietorships, the owner will be responsible for accepting and issuing invoices. However, in larger companies, such processes are handled by dedicated employees, accountants, or an external accounting firm. In order to delegate these tasks, it will be necessary to grant permissions to the appropriate people. We can grant such permissions from our application. - commercial or free and include viewing invoices, issuing them and receiving them.
KSeF tests - an important exam before starting to use the new solution
After completing all the formalities related to accessing KSeF, should we wait for the system's effective date? Not entirely. These few months are the perfect time to test the solution. How do we do this?
The minimum plan is to issue a test invoice in the demo version of the KSeF system. It is also worth making sure that the invoice has the correct format (XML) - only this format is accepted by the KSeF scheme. Finally, it's also worth fully validating the invoice. Receiving an Official Receipt Confirmation (UPO) will confirm that everything is in order.
KSeF in a large company - how to ensure smooth implementation of the solution and process continuity?
The introduction of KSeF is mandatory regardless of how complex and specific the business processes we implement in the company. That is why it is so important to ensure that the procedures in the company are adjusted before the legal obligation to participate in KSeF. How to do this?
Let's start with employee training. Company accountants and employees must be familiar with all the rules related to issuing and receiving invoices in the KSeF system, and it's our responsibility to ensure that employees are trained in this area. But that's not all.
It is very important for large companies using ERP systems to ensure effective integration of the IT ecosystem with the e-Invoice system.. Commercial APIs or professional support can help us with this, facilitating the integration of both solutions. Before implementing the system, it's worth analyzing sales, accounting, and customer service procedures to determine whether KSeF will require any changes.
What after the introduction of KSeF?
Does the deadline for our company to become a member of the National e-Invoice System (KSeF) absolve us from further concern about this topic? Quite the opposite! We all know how frequently regulations change. Therefore, we can expect amendments to the rules related to using the National e-Invoice System, and improvements to the solution in the future. That's why it's so important to continually expand your knowledge by participating in training courses and webinars, and following all announcements published by the Ministry of Finance.
If we make sure that our accounting system is compatible with the latest version of KSeF 2.0, we will be open to changes, the KSeF implementation process will be a pleasure for us, which in the long run will save us a lot of time and money.
If you need more information about KSeF, contact us - we will be happy to answer any questions you may have.
