The full guide
What is a digital certificate?
A digital certificate (certificado digital, or certificado de persona física) is an electronic ID file installed on your computer. It proves who you are online and lets you sign documents electronically. It’s issued for free by the FNMT, Spain’s national mint.
With it you can file tax returns, apply to renew residence permits through Mercurio, get your social security number instantly, check appointments and download official certificates without queueing.
How to get it, step by step
| Stage | What you do |
|---|---|
| 1. Request | On the FNMT website, enter your NIE, first surname and email. You’ll receive a request code. |
| 2. Identity check | Prove your identity at an accreditation office, or by video identification if available to you |
| 3. Download | Return to the FNMT site on the same computer and download the certificate |
| 4. Backup | Export a copy protected with a password |
Where to prove your identity
The traditional route is an in-person check at an accreditation office. Tax Agency (Agencia Tributaria) and Social Security offices are the most common, and some town halls also do it. Most require an appointment. Bring your request code, your TIE or NIE certificate and your passport.
The FNMT also offers identity checks by video from your phone for people with a DNI or NIE. If the option is available to you, it saves a trip, but in-person checks remain the reliable fallback for foreigners.
Digital certificate or Cl@ve?
| Option | Good for |
|---|---|
| Digital certificate | Signing documents, Mercurio applications, tax filings for autónomos |
| Cl@ve | Quick logins with a PIN on your phone for many everyday procedures |
Many people get both. See setting up Cl@ve.
Common mistakes
Switching computers. You must download the certificate on the same computer and user account you used to request it.
Forgetting the password. If you lose the request password, you have to start again.
No backup. If your laptop dies, a backup file saves you from repeating the whole process.
Letting it expire. You can renew online before expiry. After it expires, you start from scratch.
Frequently asked questions
Is the digital certificate free?
Yes. The FNMT personal certificate is free.
Can I use it on my phone?
Yes. Once you have the backup file, you can install it on other devices, including phones.
Do I need a TIE to get one?
You need an NIE. Bring your TIE or NIE certificate and passport to the identity check.
Official sources
FNMT: personal digital certificate
Ministry of Justice: getting an FNMT certificate by video identification
