KSeF 2026 – Why a qualified electronic signature is the foundation of deployment
KSeF 2026 – what will change for businesses?
From 1 February 2026 for large companies, and from 1 April for all remaining economic entities, using the National e-Invoice System (KSeF) will be mandatory. For many businesses this means a revolution in daily document workflows. Although KSeF provides centralized issuing and receiving of invoices, it does not solve every challenge. A key tool that enables preparation for the change is the qualified electronic signature.
Role of the electronic signature in KSeF
Authorization in the KSeF system can be done in several ways: via a KSeF token, Trusted Profile, electronic seal, or a qualified electronic signature. In practice, the qualified signature is the most reliable option because:
it has legal force equivalent to a handwritten signature (in accordance with eIDAS),
it allows user authentication in KSeF,
it can also be used in other e-administration systems (ZUS, KRS, CEIDG),
it guarantees the security and integrity of documents.
What benefits does early adoption of a qualified signature bring?
Security – the signature eliminates the risk of forgery and confirms document authenticity.
Universality – once implemented the signature works not only in KSeF but also in interactions with public administration.
Quick issuance – in local points such as Bydgoszcz the signature can be obtained in as little as 30 minutes.
Time savings – electronic signing of invoices, contracts and letters removes the need to print and post documents.
Future readiness – the signature is part of broader document digitization that goes beyond KSeF.
Case study: a small regional company
A sample company from Bydgoszcz, preparing for KSeF, decided to implement a qualified electronic signature. As a result:
the owner could independently authorize invoices in KSeF,
accounting streamlined document workflows without printing,
the company gained a tool to sign contracts with clients online.
Importantly, the entire process—from ordering to activation—took less than one hour.
Qualified signature vs other KSeF authorization methods
Trusted Profile – free but time-limited and functionally limited.
KSeF token – practical but requires additional configuration and is not a universal solution.
Electronic seal – better for large companies and automation, but less flexible for sole proprietorships.
Qualified electronic signature – the most versatile tool, suitable for sole traders and large corporations alike.
Summary and plan of action
KSeF 2026 is an obligation that cannot be postponed. A qualified electronic signature not only eases entry into the system but also opens the door to full document digitization. The best time to implement the signature is now—to avoid time pressure in 2026.
👉 Check our electronic signature offers in Bydgoszcz and order your certificate — even in 30 minutes.
Fill in the form — we will advise the best qualified electronic signature or electronic seal. Local point: electronic signature Bydgoszcz. Readiness for KSeF 2026 starts today.