Electronic signatures: a digital expression of intent

Comparison of electronic and digital signatures with use cases.

An electronic signature is any digital method a person uses to express their intent—essentially confirming agreement with a document. It replaces a handwritten signature but does not necessarily include technical safeguards.

Common Examples of Electronic Signatures:

✅ Scanned signature
An image of a handwritten signature is inserted into a document.

✅ Clicking "OK" or checking a box
Agreeing to terms and conditions by clicking a checkbox.

✅ Email confirmation
Confirming an agreement by responding to an email.

✅ Basic PDF signatures
Signing with a mouse or touchscreen without additional security measures.

These methods fall under Simple Electronic Signatures (SES) and indicate the signer’s intent. While they are convenient for everyday use, they can be easily forged or manipulated and may not be legally valid depending on the required formality.

Digital signature: cryptographic security

While an electronic signature is a declaration of intent, a digital signature is a technical mechanism that ensures a document’s authenticity and integrity. It relies on asymmetric encryption with a public-private key pair to verify that a document has not been altered.

Common use cases for digital signatures (Which are not electronic signatures) include:

✅ Code Signing
Software developers and companies use digital signatures to ensure the authenticity and integrity of programs and updates. Code signing guarantees that the software has not been tampered with and originates from the stated developer.

✅ TLS/SSL Certificates
TLS/SSL certificates act as digital signatures for websites, ensuring that a connection is secure and that the website is legitimate. Without digital signatures, secure web communication—including online banking and e-commerce—would not be possible.

✅ Blockchain Transactions
In blockchain networks like Bitcoin and Ethereum, digital signatures authenticate transactions. Each transaction is signed with a private key, ensuring that only the rightful owner of the cryptocurrency can transfer it.

Digital signatures are about security, not intent.

Digital signatures provide security and trust in digital processes, but they do not express intent or legal consent. They are a technical security tool, not an electronic signature in the legal sense.

When is an electronic signature legally binding?

Electronic signatures make it easier to execute contracts and documents digitally. However, for an electronic signature to be legally valid, it must be combined with a digital signature and meet specific legal requirements.

The legal framework for electronic signatures is defined by the eIDAS Regulation in the European Union and ZertES in Switzerland. Both systems classify electronic signatures into three levels:

• Simple Electronic Signature (SES) – No specific security requirements

• Advanced Electronic Signature (AES) – Uniquely linked to the signer and protected against tampering

• Qualified Electronic Signature (QES) – The highest security level, legally equivalent to a handwritten signature

A Simple Electronic Signature (SES) is the most basic form and does not require technical safeguards. A Advanced Electronic Signature (AES) offers more security because it is uniquely linked to the signer and protects against unauthorized alterations. The Qualified Electronic Signature (QES) is the highest level and is legally equivalent to a handwritten signature in both the EU and Switzerland.

Cross-Border Challenges

One key challenge is the cross-border recognition of electronic signatures. Despite their high-security standards, EU-QES and Swiss-QES are not automatically recognized in each other’s legal systems. A document signed with a qualified Swiss certificate is not necessarily accepted as a QES in the EU—and vice versa.

If you operate across both jurisdictions, make sure your signature solution is compliant with both eIDAS and ZertES.

Final thoughts: electronic vs. digital signatures

Many people confuse these terms—but understanding the difference is crucial. An electronic signature is a digital expression of intent, while a digital signature is a cryptographic process ensuring data integrity. Not every digital signature is an electronic signature—but an electronic signature can be secured with a digital signature.

And if you need it to be legally binding? Then a Qualified Electronic Signature (QES) is the only way to go. fidentity provides a certified signature solution that meets the highest security standards and is fully compliant with eIDAS and ZertES—ensuring your digital signatures truly count.

Learn more about signature validation and legally binding QES in this blog!