Qualified Electronic Signature: Meaning and Requirements

What is a qualified electronic signature?

A qualified electronic signature (QES) is an advanced electronic signature based on a qualified certificate and created using a qualified electronic signature creation device (QSCD), under EU eIDAS rules.

Article 25 gives QES the equivalent legal effect of a handwritten signature across EU Member States. That equivalence does not remove other requirements for the document, such as a required witness or the signer's authority to represent a company.

What makes a signature qualified?

The certificate must be qualified, not simply described as a digital certificate. Its qualified trust service provider and service status can be checked against the relevant EU trusted list. The QSCD protects signature-creation data and may be managed remotely; the signer does not necessarily hold a USB token.

The European Commission's qualified-signature guidance explains these distinctions. An ordinary completion record, a handwritten-looking mark or use of a digital signature does not, by itself, establish qualification.

When is QES needed?

Check the applicable law, document and recipient requirements. Not every agreement needs QES, and a simple electronic signature can have legal effect. Qualification identifies a specific level of electronic signing; it is not a blanket guarantee that every agreement is valid.