What is a qualified electronic signature (QES)?
A qualified electronic signature (QES) is the highest of the three levels of electronic signature in the EU's eIDAS Regulation. It's an advanced electronic signature created with a qualified signature creation device and based on a qualified certificate from a qualified trust service provider. In the EU, a QES has the same legal effect as a handwritten signature.
Also called: QES, Qualified e-signature, eIDAS qualified signature
Updated October 15, 2026 · By the PDFZyro team
How a QES differs from other e-signatures
eIDAS recognizes three levels. A simple electronic signature is any electronic sign of agreement, such as a typed name or a drawn signature. An advanced electronic signature (AES) must also be uniquely linked to the signer, identify them, be made with means under their sole control and reveal any later change to the document. A QES adds two things: a qualified trust service provider verifies the signer's identity before issuing a qualified certificate, and the signature is made with a certified device, such as a smart card or a remote signing service run by the provider.
What the law says
Under eIDAS, an electronic signature can't be refused as evidence just because it's electronic, but only a QES automatically has the same legal effect as a handwritten signature, and a QES based on a qualified certificate from one EU member state is recognized in all the others. Qualified trust service providers are supervised and listed on the EU Trusted Lists. eIDAS was updated in 2024 by Regulation (EU) 2024/1183, and the United Kingdom and Switzerland have similar rules of their own.
Most everyday contracts don't need a QES: a simple or advanced signature with good evidence is usually enough. A QES matters mainly where national law requires a written or handwritten signature for a particular document, or where an authority or the other party asks for one. The rules differ by country and by document, so this is general information, not legal advice: ask a lawyer if you're not sure which level you need.
How people get a QES
A QES comes from a qualified trust service provider. After an identity check, for example in person, by video or with a national eID, the provider issues a qualified certificate on a card or token, or lets you sign through its remote signing service. Outside the EU, a QES is still a strong signature, but other countries apply their own rules to it.
QES and electronic signatures in PDFZyro
- PDFZyro doesn't offer qualified electronic signatures: it isn't a qualified trust service provider, and signing with a Digital ID file in PDFZyro doesn't create a QES.
- For documents that don't need a QES, send a signature request: each signer agrees to sign electronically and can be checked with an access code or a text-message code, and you get a sealed PDF, an audit trail and a certificate of completion.
- If you receive a PDF signed with a QES, open it with Check signatures to see who signed, the certificate and whether the document changed afterwards. To confirm that a signature is qualified, use an eIDAS validation service.
Tools and guides
Related terms
- Advanced electronic signature (AES)The middle level of e-signature under eIDAS: linked to one signer and tamper-evident.
- Electronic signature (e-signature)Any electronic sign that shows a person agrees to a document, from a typed name to a drawn signature.
- Digital ID (signing certificate)A certificate and a private key that identify you and let you add digital signatures to PDFs.
- Digital signatureA cryptographic, certificate-based seal that shows who signed a file and that it hasn't changed.