A Practical KSeF Checklist for Your Company in Poland
October 17, 2025
Overview
From April 2026 all VAT registered entities in Poland must issue, send and receive invoices through the National Electronic Invoicing System known as KSeF. The platform centralizes invoicing and removes the need for paper and manual formats.
The system registers each invoice at the moment of issuance. After registration you cannot delete the document or change it retroactively. This requires greater discipline and clear internal control before any invoice goes out.
Official information and materials are available on the website of the Polish Ministry of Finance:
Ministry of Finance KSeF materials
KSeF implementation checklist
1. Register your company in KSeF
First link your tax identification with the platform so that your company can issue and receive structured invoices within the system.
2. Register your employees who will issue invoices
Authorize each person who prepares or sends invoices. Make sure you granted access rights to all employees who need them to issue documents on behalf of the company.
3. Authorize your accounting firm
Provide your accountant with access to retrieve both sales and purchase invoices. The safest setup uses passive access for reading and downloading documents while your company keeps control of issuing.
4. Choose and configure compatible invoicing software
KSeF accepts only structured XML invoices submitted through integrated software. Documents prepared in Word, Excel or on paper will not be valid for business use. Verify that your current program supports KSeF integration and test the connection in advance. Tools such as SaldeoSMART already provide full compatibility.
5. Implement a monthly internal procedure for invoice review
Set a routine to review all incoming invoices each month. Confirm that every document relates to business activity and classify it correctly for accounting and tax purposes. Not every invoice visible in KSeF qualifies as a deductible cost. For example a supplier can issue an invoice to your company NIP by mistake even when the purchase is not related to your activity. Such invoices must be identified and excluded before booking.
Practical implications
You cannot create invoices in Word, Excel or PDF and send them by email as the primary method for business transactions. Each invoice is timestamped and registered automatically within KSeF. If you find an error you must issue a formal correction rather than replace the document.
The change increases discipline yet brings clear benefits. It reduces the risk of lost documents, supports automation with accounting software and secures tax records. It can also support better tracking of payments and VAT settlements.
Frequently asked questions
When does KSeF become mandatory
KSeF becomes mandatory for all VAT registered businesses from April 1, 2026. Larger entities with annual turnover above PLN 200 million must comply from February 2026.
Can I still issue invoices in Word or Excel
No. After the obligation starts you must use software that integrates with KSeF to issue structured electronic invoices.
How do I authorize my accounting firm
Log in to KSeF and assign access rights to your accountant. Passive access lets them read and download documents while your company retains control of issuing.
What if an invoice contains an error
Since invoices are registered at issuance you cannot delete or alter them. Use a formal correction invoice to address mistakes.
Does KSeF cover all transactions
The obligation covers domestic business to business transactions. Business to consumer use remains voluntary within KSeF.
Jerzy Gaweł
Partner – Tax Advisor
