Electronic Signatures in Switzerland and the EU

Printing contracts, signing by hand, scanning them back and mailing the originals — for many businesses this is still standard practice. Yet a legally equivalent alternative has existed for years: the electronic signature. But which legal frameworks apply in Switzerland and the EU? Which signature level suits which use case? And what changes does eIDAS 2.0 bring? This article provides a comprehensive overview.

Legal Foundations at a Glance

ZertES — the Swiss Legal Basis

In Switzerland, the Federal Act on Certification Services in the Area of Electronic Signatures and Other Applications of Digital Certificates (ZertES) has governed the use of electronic signatures since 2003. The current version dates from 18 March 2016. The act defines the requirements for certification service providers — known as Trust Service Providers (TSPs) — and sets out when an electronic signature carries the same legal weight as a handwritten one.

Key aspects of ZertES:

• It defines three quality levels for electronic signatures (SES, AES, QES)
• It regulates the recognition and supervision of Trust Service Providers in Switzerland
• The qualified electronic signature (QES) is legally equivalent to a handwritten signature, provided it is based on a qualified certificate issued by a recognised provider and combined with a qualified timestamp (CO Art. 14 para. 2bis)

eIDAS — the European Counterpart

In the European Union, the eIDAS Regulation (Electronic Identification, Authentication and Trust Services) serves the same purpose as ZertES. The original Regulation (EU) No 910/2014 took effect in 2016 and created the first unified legal framework for electronic signatures, seals, timestamps and trust services across all EU member states.

The eIDAS Regulation recognises the same three signature levels as ZertES. One key difference: within the EU, qualified electronic signatures enjoy automatic cross-border recognition. Every member state must accept a QES created in any other member state as valid.

eIDAS 2.0 — What Changes from 2026

In May 2024, Regulation (EU) 2024/1183 — commonly known as eIDAS 2.0 — entered into force. It introduces far-reaching changes that are being implemented in phases through to the end of 2026.

The most important changes:

• EU Digital Identity Wallet (EUDI Wallet): By December 2026, every member state must provide its citizens and residents with at least one digital identity wallet. This wallet will store government-verified identity credentials, professional qualifications and other attributes that can be shared selectively with trusted services.
• Expanded trust services: Beyond signatures and seals, eIDAS 2.0 now also covers electronic attestation of attributes, qualified electronic archiving and electronic ledgers.
• Wallet-based signature creation: Qualified Trust Service Providers will be able to draw on identity data directly from the EUDI Wallet, significantly accelerating the issuance of qualified certificates.
• Mandatory acceptance: From late 2027, certain private-sector actors and very large online platforms must accept EUDI Wallets for authentication purposes.

Switzerland and the EU — No Mutual Recognition Yet

Although ZertES and eIDAS share a similar structure, there is currently no official mutual recognition of electronic signatures between Switzerland and the EU. This means a QES created in Switzerland is not automatically recognised as such in the EU — and vice versa.

On 29 January 2025, the Federal Council instructed DETEC and the FDFA to draw up a negotiating mandate for mutual QES recognition within one year. Until such negotiations are concluded, businesses with cross-border signing needs should rely on pragmatic solutions — for example, Trust Service Providers that are recognised under both ZertES and eIDAS.

The Three Signature Levels

Both ZertES and the eIDAS Regulation distinguish three levels of electronic signatures. They differ in the degree of identification required, their evidential value and their legal standing.

SES — Simple Electronic Signature

The simple electronic signature (SES) is the lowest level. The signer is identified solely by their email address. No further identity verification takes place.

Evidential value: Low. In the event of a dispute, the party relying on the signature must prove its authenticity.

Typical use cases:

• Internal approvals and sign-offs
• Meeting minutes
• Delivery notes and acknowledgements of receipt
• General business correspondence

AES — Advanced Electronic Signature

The advanced electronic signature (AES) offers a considerably higher level of assurance. The signer is identified by their email address and mobile phone number. This two-factor combination ensures the signature is uniquely linked to a specific person and can only be created by that person. Any subsequent changes to the document are also detectable.

Evidential value: Medium to high. The link to a verified mobile number significantly strengthens the ability to prove authenticity.

Typical use cases:

• Employment contracts and references
• Rental and lease agreements
• Purchase orders and order confirmations
• General terms and conditions

QES — Qualified Electronic Signature

The qualified electronic signature (QES) is the highest level and — when combined with a qualified timestamp — is legally equivalent to a handwritten signature (CO Art. 14 para. 2bis) — under both ZertES and eIDAS. It requires strong two-factor authentication to verify the signer's identity and is based on a qualified certificate issued by a recognised Trust Service Provider.

Evidential value: Very high. The burden of proof shifts to the party contesting the signature's authenticity — not the party relying on it.

Typical use cases:

• Consumer credit agreements (CCA Art. 9) and contracts with statutory written form requirements
• Corporate resolutions and powers of attorney
• Audit-relevant documents
• Official submissions

Important: Not all high-requirement legal acts can be completed with QES. Surety declarations require the surety's own handwritten signature and handwritten specification of the maximum liability amount (CO Art. 493). Real estate purchase agreements require notarial authentication (CO Art. 216) — QES replaces neither the signer's own hand nor notarial authentication. Holographic wills must be handwritten in full and signed by hand (CC Art. 505).

Levels of Assurance and Regulatory Classification

The three signature levels map to the levels of assurance defined by both the eIDAS Regulation and international standards such as ISO 29115:

Important: choosing the right signature level depends not only on the desired security but also on the legal requirements of the specific transaction. In Switzerland, the Code of Obligations prescribes written form for certain contract types — only a QES combined with a qualified timestamp fulfils this requirement. Where the law requires the signer's own hand (e.g. surety declarations, holographic wills), even QES is not sufficient.

Practical Implications for Businesses

Why SMEs Benefit in Particular

For small and medium-sized enterprises, electronic signatures are more than a technical tool — they represent a genuine competitive advantage:

• Faster contract completion: Instead of waiting days for postal delivery, contracts are signed and returned within minutes.
• Cost reduction: Printing, postage and physical archiving costs are largely eliminated.
• Legal certainty: Every signing event is logged end to end and can be audited at any time.
• Location independence: Contracts can be signed from anywhere — the office, home or on the move.

The Right Level for the Right Purpose

Not every document requires a QES. Many everyday business processes can be concluded legally with an SES or AES. The rule of thumb: the higher the financial risk and the stricter the legal form requirements, the higher the signature level should be.

Ensuring Compliance

Businesses using electronic signatures should pay attention to the following:

• Recognised Trust Service Provider: Signatures must be created through a recognised certification service provider — in Switzerland, for example, Swisscom Trust Services.
• Documentation: The entire signing process should be fully documented, including timestamps and proof of identification.
• Archiving: Signed documents should be stored in an audit-proof archive.
• Cross-border transactions: For international contracts, it is advisable to use a Trust Service Provider that is accredited under both ZertES and eIDAS.

actaSIGN — All Signature Levels on One Platform

actaSIGN is a Swiss signing platform that supports all three signature levels (SES, AES, QES) and is fully ZertES-compliant. As an Approved Partner of Swisscom Trust Services, users benefit from an established Trust Service Provider recognised both in Switzerland and internationally.

Whether a simple internal approval or a qualified signature with full legal effect — with actaSIGN, businesses choose the right signature level for every document.