What is KSeF?
The National e-Invoice System (KSeF) is Poland's centralized platform for issuing, receiving, and storing structured electronic invoices. Starting February 1, 2026, all active VAT taxpayers must use KSeF for their invoicing.
Who is affected?
- All active VAT taxpayers in Poland
- Foreign companies with Polish VAT (NIP) registration
- Companies using the OSS procedure
- Micro-entrepreneurs (phased implementation)
How to authenticate in KSeF?
One of the primary authentication methods is using a Qualified Electronic Seal (QSeal) linked to your company's NIP number. This is the recommended method for companies, especially those with multiple users who need to access the system.
What do you need to prepare?
- Obtain a Qualified Electronic Seal linked to your company NIP
- Update your invoicing software to support KSeF structured format
- Train your accounting team on the new e-invoicing workflows
- Test the integration before the mandatory date
How can we help?
As an authorized Certum partner, Trust Services provides complete KSeF readiness support — from issuing your Qualified Electronic Seal to guiding you through the integration process. Remote video verification is available for foreign company representatives.
Contact us to get started with your KSeF preparation today.