Can I sign a suretyship (guarantee) declaration electronically?

No — for a private suretyship declaration, § 766 of the German Civil Code (BGB) requires statutory written form: the guarantor's declaration must be made in writing, with a handwritten signature. This page describes German and EU law specifically; rules differ elsewhere. A Simple Electronic Signature (SES), the kind SignSent creates, does not meet this requirement — a suretyship declaration signed electronically without QES would be void for lack of form.

The reason for this strict form requirement is protection against rash decisions: a suretyship obligates the guarantor to pay someone else's debt, often a substantial amount, and frequently arises out of personal closeness (family, close friendship) rather than economic judgment. The legislator wants to prevent someone from taking on such a far-reaching obligation carelessly or under social pressure — the handwritten signature on paper is meant to force a deliberate moment of pause.

§ 126(3) BGB would generally allow statutory written form to be replaced by electronic form — but only a Qualified Electronic Signature (QES) under eIDAS is permitted for that, not a Simple Electronic Signature. SignSent does not currently offer QES.

An important exception: if the suretyship is a commercial transaction for the guarantor (§ 350 of the German Commercial Code — meaning the guarantor is acting as a merchant within their commercial business), the written-form requirement of § 766 BGB does not apply at all. In that narrowly defined case, a form-free — and therefore electronically signed — suretyship could in principle be valid. Whether a specific case falls under this exception is a legal question that should be checked with a lawyer before relying on it.

In practice: for the vast majority of private suretyships (for example, a parent guaranteeing a child's apartment lease, or a personal guarantee given to a bank), a handwritten signature on paper is required. SignSent is deliberately not the right tool for this. Concretely, that means printing the suretyship declaration, signing it by hand with ink, and handing over the original to the beneficiary or sending it by post — a scanned or emailed copy of a handwritten signature does not satisfy the written-form requirement itself; only the signed paper original counts. The only electronic alternative that § 126(3) BGB permits at all is a Qualified Electronic Signature (QES) issued through an eIDAS-certified trust service provider, where the provider verifies the signer's identity and signs cryptographically with a certificate tied to that identity. SignSent deliberately does not offer such a certificate-based QES service, since it requires its own costly identity-verification infrastructure that most everyday contracts (see the other contract types in this overview) don't need at all.