Cl@ve and the digital certificate if you lose your phone
Cl@ve is Spain's identity system for dealing with the Spanish government, for residents with a Spanish ID (DNI/NIE). Cl@ve PIN, meant to be the fast lane, actually sends the code to your phone just like the "complicated" one. The route that really doesn't need your phone is a different one: Cl@ve Permanente without the extra step, or the digital certificate.
Short version: Cl@ve has several doors (Cl@ve PIN, Cl@ve Permanente, the Cl@ve app, the digital certificate and the DNIe) and they don't all depend on your phone equally. If you only have Cl@ve PIN or the app turned on, you're more tied to your phone than it seems. It's worth having at least one more path active before a deadline forces you to improvise.
Why this matters
Cl@ve is the system you use to identify yourself to the Spanish government: the Tax Agency, Social Security, the Electronic Office and most online paperwork with town halls and ministries. For many of these procedures, there's no alternative without an in-person appointment: if you can't log in, you can't get the paperwork done on time.
The problem with Cl@ve is different from Google or Apple's: here there's no quick recovery form or trusted contact. If you can't identify yourself through any method, the alternative is usually booking an in-person appointment, which during campaigns like the annual tax return can take weeks to get. That's why it's worth having more than one method active with the government long before a procedure has a deadline looming.
What Cl@ve asks for from a new phone
Cl@ve PIN requires you to have registered beforehand and, every time you use it, you get a code with limited validity through the Cl@ve PIN app or by SMS: you need your phone no matter what to complete the step. It's designed for people doing occasional paperwork, not for those who need to log in often. The Cl@ve app (Cl@ve Móvil) works similarly: you confirm access with a QR code, a push notification in the app or, as a fallback, a PIN by SMS. It also depends on the phone where you have it installed, and on that phone still being the one you registered.
Cl@ve Permanente is different: you identify yourself with your DNI or NIE and a password you chose yourself. For most basic-level procedures, that's enough, without asking your phone for anything. Only for higher security-level procedures does Cl@ve Permanente add a one-time code sent by SMS to your phone as a second factor. In practice, this means many people who think they depend on their phone for everything actually only depend on it for part of their paperwork, and don't know it because they've never tried logging in without it.
The routes that really don't depend on your phone
If what you want is to not depend on your phone at all, the two real options are: using Cl@ve Permanente for procedures that don't require that SMS second factor, and having a digital certificate (from FNMT or another provider) installed on a computer, or a DNIe (Spanish electronic ID) with its PIN and a card reader or an NFC-compatible phone. Neither asks your phone number for anything.
The FNMT personal digital certificate is downloaded once, after proving your identity (in person at an authorized office, or through whatever alternative methods FNMT publishes), and from then on it lives on the computer or browser where you installed it, not in a phone app. That comes with a trade-off: if you switch computers, you have to export it again or request a new one, just like with any important file you only have saved in one place.
The DNIe has the advantage of being physical and not depending on any prior online registration beyond having the document itself valid and its PIN set up. The downside is you need a card reader connected to a computer, or an NFC-capable phone with the right official app, so it isn't instant either if you've never tried it before you needed it.
What to check today
- Do you have Cl@ve Permanente (username and password) turned on, not just Cl@ve PIN?
- Do you know whether the procedure you usually need requires the SMS second factor or not?
- Do you have a digital certificate installed somewhere that doesn't depend only on your phone?
- Do you know where your DNIe PIN is if you need it?
- Have you ever tried using your DNIe or certificate before you actually needed it?
If you can no longer get in
If the problem is that the Cl@ve Permanente SMS isn't arriving, first check whether the specific procedure has a path without that step. For questions about registering for or accessing Cl@ve, official help is at clave.gob.es. If what you need is the DNIe and you don't have the physical card on hand, that process goes through the National Police, not Cl@ve.
If the procedure is urgent and you really can't identify yourself through any electronic method, the alternative that still exists is in person: a registry office or citizen services office, with an appointment if the agency requires one. It's not fast, but it's the safety net that remains when everything digital fails at once, and it's worth knowing it exists before you need it in a hurry.
Official sources (Spanish-language, Cl@ve is a Spanish government system with no English help pages): What is Cl@ve PIN · What is Cl@ve Permanente · What is Cl@ve Móvil