If a structured invoice in KSeF is issued with an incorrect buyer NIP, a “zeroing” corrective invoice must be issued (structured or offline), then a new invoice with the correct NIP must be created. From...

The date of invoice issuance in KSeF is the date in field P_1, not the date the invoice is created in the system. This date is also the date the tax obligation arises if the invoice date matches the delivery date. The...

Only a few dozen people nationwide will have access to all KSeF data, and only with a special “secret” clearance. Details about KSeF security are withheld to prevent hackers from exploiting information. KSeF...

Concerns are rising about the security of invoice data in the National e-Invoice System (KSeF) as its launch approaches. Users worry that a private company, Imperva (owned by Thales), which provides cybersecurity...

From February 1, 2026, all taxpayers must receive invoices via the National e-Invoice System (KSeF). Employees making purchases on behalf of employers need to understand new documentation rules, as various invoice types...

The MCU (Module of Certificates and Permissions) in KSeF allows companies to manage access rights, apply for, and download KSeF certificates, which are necessary for issuing and receiving invoices. Early login to MCU...

In 2026, taxpayers with monthly sales documented by invoices not exceeding 10,000 PLN (gross) are exempt from mandatory KSeF e-invoicing and can issue invoices using previous methods. The 10,000 PLN limit includes only...

In 2026, “phantom invoices” (documents pretending to be VAT invoices) will appear in the KSeF system. There will be confusion due to invoices being sent to KSeF after already being issued and received...

Concerns have resurfaced about the security of the National e-Invoice System (KSeF) due to a social media post. The Ministry of Finance assures that invoice data is properly encrypted and secure. Experts question the...