KSeF mandatory since when? Deadlines 2026/2027 for JDG and companies
Current dates of mandatory entry into the KSeF and a practical action map for micro, small and medium-sized enterprises.
Key implementation dates
The National e-Invoice System is being implemented in stages. For the largest entities, the obligation began on February 1, 2026. For other VAT taxpayers, the obligation begins on April 1, 2026.
Additionally, the group of entities referred to as digitally excluded has an extended transition period until January 1, 2027. In practice, this means that most companies should treat March 2026 as the last moment for production tests.
- •February 1, 2026: entities with turnover above PLN 200 million.
- •April 1, 2026: other entrepreneurs covered by the obligation.
- •January 1, 2027: digitally excluded entities.
What does this mean for JDG and SMEs?
For JDG, the greatest risk is not the KSeF system itself, but the lack of consistent procedures in document circulation. Some companies have separate tools for issuing invoices, separate ones for accounting and separate ones for reporting.
If these systems do not exchange data automatically, the company begins to manually correct documents, which directly increases operational costs and the risk of errors.
- •Verify which processes are manual today.
- •Check who is responsible for errors in invoices.
- •Establish a contingency plan for the implementation period.
Action plan for 30 days
In the first week, it is worth preparing a map of the process: from issuing an invoice to its posting and settlement. You then need to specify where the data is copied manually.
In the second and third weeks, the company should run test scenarios for sales invoices, corrections and exceptions. The last week is the stage of stabilization, monitoring and user training.
- •Week 1: process and roles audit.
- •Week 2-3: Document and proofreading tests.
- •Week 4: procedures, monitoring, training.