Are electronic signatures legal in Spain? Ley 6/2020, FNMT and DNIe

Spain is one of the easiest places in Europe to sign documents digitally. Millions of people hold a free FNMT certificate on their computer and use it for tax returns and dealings with the administration. Rental agreements, employment contracts and business deals are signed online every day.

But there are still a few places where Spanish law wants a notary, and a nuance about FNMT certificates that most guides get wrong. This article covers both.

The short answer

• Electronic signatures are legally valid in Spain under the EU eIDAS Regulation and Ley 6/2020, de 11 de noviembre, reguladora de determinados aspectos de los servicios electrónicos de confianza.
• The Código Civil makes most contracts binding whatever form they take, so any electronic signature can form a valid contract.
• A qualified electronic signature (QES) has the same effect as a handwritten one, and documents signed using qualified trust services are presumed genuine if challenged in court.
• The FNMT citizen certificate is a qualified certificate, but when it is installed as a software file, signatures made with it are advanced signatures based on a qualified certificate, not QES.
• Transfers of land for the Property Registry need an escritura pública before a notary. A holographic will must be written by hand.

The law

Ley 6/2020 and eIDAS

Ley 6/2020 replaced the old Ley 59/2003 de firma electrónica to adapt Spanish law to eIDAS. Its article 3 says electronic public, administrative and private documents have the legal value that corresponds to their nature, under the applicable law. The law also:

• allows qualified certificates for electronic signatures only for natural persons; companies use electronic seals or representative certificates;
• sets identity-verification rules for issuing qualified certificates, including remote video identification under conditions; and
• names the ministry responsible for digital transformation as the supervisory body, which keeps the Spanish trusted list.

Evidence: the Ley de Enjuiciamiento Civil

Ley 6/2020 amended article 326 of the Ley de Enjuiciamiento Civil. If a party challenges an electronic document that was made using a qualified trust service listed on the trusted list, the document is presumed to have the challenged quality (authenticity, integrity, date) and the challenger bears the cost of checking it. For other electronic signatures, the court weighs the evidence, and the audit trail does the work.

Freedom of form in the Código Civil

Under article 1278 of the Código Civil, contracts are binding in whatever form they are concluded, as long as the essential conditions are met. Article 1280 lists acts that must be put in a public document (such as those creating or transferring rights over real property), but under article 1279 that requirement lets either party compel the other to formalise the deal; it does not generally make a private contract void. In practice, you still need the public document to register the transfer.

Documents you cannot sign electronically (or need a special signature)

Property

To register a sale or mortgage in the Registro de la Propiedad, the transaction must be in a public document, in practice an escritura signed before a notary. The earlier private purchase contract (contrato de arras or compraventa privada) can be signed electronically, but it will not get you onto the Registry.

Spanish notaries work electronically among themselves and with the registries. More recent reforms, notably Ley 11/2023, introduced notarial acts by videoconference for some documents, such as certain company acts and powers of attorney; wills and property sales are generally outside that route. Ask the notary which procedure applies.

Wills

Under article 688 of the Código Civil, a holographic will may only be made by adults, and must be written entirely and signed by the testator's own hand, with the date. It must later be verified before a notary after death. An open will made before a notary is the more common choice. Neither can be replaced by an electronic signature.

Common situations

Employment contracts

Spanish employment contracts may be written or verbal in general, but several types (fixed-term, part-time, training contracts and others) must be in writing. An electronic signature satisfies that. Employers commonly send contracts through e-signing platforms; the contract is then communicated to the public employment service through its own system.

Leases

The Ley de Arrendamientos Urbanos leaves the form of a lease open, and either party can require it to be put in writing. E-signed rental contracts are common. The deposit must still be lodged with the regional body where required.

Dealing with the administration

Ley 39/2015 on common administrative procedure lets citizens identify themselves and sign before the public administrations with systems such as qualified electronic certificates, the DNIe and Cl@ve. Each office's electronic headquarters (sede electrónica) sets which methods it accepts. The Agencia Tributaria and Seguridad Social accept the FNMT certificate and Cl@ve.

How to get a digital certificate in Spain

FNMT citizen certificate (certificado de persona física)

The Fábrica Nacional de Moneda y Timbre (FNMT-RCM) issues a free citizen certificate to anyone with a DNI or NIE. You request it online using FNMT's configuration software (the Configurador FNMT-RCM), prove your identity at an accreditation office, with your DNIe or by video identification (the only option that carries a small fee), and then download it onto the same computer. It is valid for four years.

Two points matter:

• It is a qualified certificate. FNMT issues it under the eIDAS policy for qualified certificates for natural persons and is on Spain's trusted list.
• The software version is not a QES. When you get it as a software certificate, the key is generated on your own computer, not on a qualified signature creation device (QSCD). Signatures made with it are therefore advanced electronic signatures based on a qualified certificate. That is strong evidence (the LEC presumption for qualified trust services is widely relied on) but in strict eIDAS terms it is not a QES.

FNMT recommends making a backup copy, which you export from your browser or your computer's certificate store as a .pfx or .p12 file protected by a password. That file is exactly what KovaPDF's Digital Signature tool uses.

DNIe

The electronic national ID card carries signing certificates on its chip. Because the chip is a secure device, signatures made with it are generally treated as qualified. You need a card reader or an NFC phone and the official software; the key cannot be exported, so the DNIe cannot be used on a website like KovaPDF.

Cl@ve and Cl@ve Firma

Cl@ve is the administration's identification system (PIN, permanent password or app). Cl@ve Firma lets you sign in administrative procedures with a certificate held centrally by the administration, in the cloud. It is designed for dealing with public bodies, not for signing private PDFs.

Doing it with KovaPDF

• [Digital Signature](/digital-signature-pdf): if you have an FNMT certificate backup (.pfx or .p12), upload it with its password and sign any PDF. You get a PAdES signature, a trusted timestamp by default and long-term validation data, so Adobe and other readers can check it for years. The certificate and password are used once in memory and not stored. The result is an advanced signature based on FNMT's qualified certificate. The same level as signing with the installed FNMT certificate in AutoFirma or your browser, not a QES.
• [Request Signatures](/request-signatures): for leases, employment contracts, NDAs and other private contracts where freedom of form applies. Each signer gets a private link and signs without an account; everyone receives the signed PDF with a certificate of completion and a trusted timestamp. These are simple electronic signatures with evidence, not certificate-based signatures.
• [Sign PDF](/sign-pdf): draw or type a signature on a form you sign alone.
• [Verify PDF Signature](/verify-pdf-signature): check a PDF signed with FNMT, a DNIe or any other certificate: integrity, signer, chain and timestamp.

For notarial deeds, handwritten wills and administrative procedures that require their own sede electrónica, use those channels.