What is a Digital Certificate?

A Digital Certificate (DC) is a digital file created as an extension of your NIE, TIE, or DNI in Spain. It is used to securely access and sign documents on Spanish government websites such as SES Hospedajes, SEDE, the Tax Office, and others.

A DC is an encrypted file — meaning it is secured using something you have (the certificate file itself) and something you know (a password). This is Two Factor Authentication (2FA). Think of it like your bank card and PIN: without both, neither is useful.

A DC is not a viewable document like a PDF. It is a file with the extension .p12 or .pfx. When you receive it, you download it to your computer and install it to access the government sites above.

Unless you need to access Spanish government sites yourself, there is no immediate need to install your DC. The most common uses are:

• Registering your property with SES Hospedajes (required to operate a holiday rental)
• Providing it to your Spanish accountant so they can file tax returns on your behalf
• Accessing SEDE and other government portals directly

Autofirma is a piece of software that works with your DC to digitally sign data. Certain actions on SES Hospedajes — such as registering your property — require you to sign for the data electronically. Autofirma is your digital signature.

If you are registering your own property with SES Hospedajes, you will need to install Autofirma in addition to your DC. It supports Windows, Mac, and Linux — but not iPad, iPhone, or Android.