MiDNI at Check-In: Accepting Spain's Digital ID Is Mandatory

A guest reaches your front desk, pats their pockets and pulls out a phone: they left the plastic DNI at home because they no longer need it. If reception answers by asking for the physical card, the conversation goes sideways, and the guest is the one in the right.

The change came with Royal Decree 255/2025, and it is worth reading in two pieces. Its article 13.4 gives the digital version of the DNI the same legal effect as the physical document for identification purposes, and says so expressly for dealings with public administrations and with the private sector¹. Its third transitional provision gave public and private entities twelve months from entry into force, which was 2 April 2025, to adopt the measures needed for that digital version to work properly². That window closed on 2 April 2026: there is no adaptation period left to invoke.

For anyone running tourist accommodation in Spain, the recurring worry is whether this also means rebuilding the guest-report flow. Let’s take it in order: what MiDNI is, what changes at the desk, and what stays exactly as it was.

What MiDNI is

MiDNI is the official app from Spain’s Interior Ministry and National Police that puts the Spanish national ID (DNI) on a phone. It is not a photo of the card and not a scan: it is the digital version of the document itself, fully valid for identification within Spain.

The holder activates it once with their physical DNI and its support number. From then on, when they need to identify themselves, the app generates a temporary QR code that stays active for only a few seconds. After that it expires and a new one has to be generated. That expiry is deliberate: it stops a screenshot from circulating as if it were a live document.

When you scan that QR (from another phone with MiDNI, or from the official verifier at www.midni.gob.es)³, you are not reading data stored on the guest’s phone. The app queries the unit that manages the DNI in real time and returns the information, which appears on screen for a moment and is not stored on the verifier’s device. That matters more than it sounds for anyone handling guest data: the flow is built so you never accumulate a static image of anyone’s card.

MiDNI doesn’t always show the same thing. Depending on what the guest selects, the verifier sees one of these levels:

• DNI age: photo, name, and whether the holder is of legal age. Nothing more.
• DNI simple: photo, full name, sex, and DNI validity.
• DNI complete: every field on the physical document.

For a check-in you need the complete level, because the guest report asks for more than a name. If a guest shows you only the age mode, ask them to switch to complete, the same way you would ask someone to turn a passport to the data page.

What MiDNI changes at your check-in (and what doesn’t)

The essential part fits in one sentence: you cannot refuse it. In practice, that breaks down into three concrete things.

• The front desk. Whoever handles in-person check-in must know what MiDNI is and how guests present it, the same way they recognise a passport. Recognising the QR isn’t optional.
• The data stays the same. RD 933/2021 requires the same fields as always (name, document number, date of birth, and so on), whether the data comes from a physical DNI, a passport or MiDNI.
• The report doesn’t change. SES.HOSPEDAJES receives exactly the same guest report. What changes is how identity is verified at the desk, not what is communicated to the Ministry.

That last distinction is the reassuring one. Your obligation to SES.HOSPEDAJES hasn’t lost or gained a single field. The only thing that has changed is which documents you must accept as proof of identity, and the list now includes a phone.

MiDNI cuts transcription errors in the guest report

There is a side effect that works in your favour. A whole class of SES.HOSPEDAJES rejections is born from data copied by hand off a document: a transposed digit in the support number, a date in the wrong format, a compound surname cut short.

When the data arrives digitally verified, it arrives as it is, not as it was typed. That removes the transcription class of rejections, which is not the only one: a report also bounces on a field copied correctly but left incomplete, or on an error in the portal itself. If your reports fail often, the error-code guide explains where each rejection comes from.

One caveat is worth spelling out, though. The MiDNI QR doesn’t fill in your report by magic: it is an identity check, not an automatic integration with your check-in system. The real gain shows up when the guest’s data travels in digital form from the start, without passing through a keyboard at reception. That is what step three is about.

How to prepare your check-in for MiDNI in three steps

1. Train whoever receives guests. Everyone on the team should know MiDNI is valid identification and how guests present it, including the detail of asking for the complete mode. Refusing it invites a complaint with the guest in the right.
2. Review your data flow. If you copy data by hand at the desk, MiDNI doesn’t fix your reports: the transcription error is still there. The real jump is having the data travel digitally from the guest into the report.
3. Move check-in forward. With digital check-in before arrival, guests provide and sign their data before setting foot in the property, and reception is reduced to handing over keys, with the document, physical or digital, as a seconds-long verification.

FAQ

Can I demand the physical DNI if the guest brings MiDNI? No, you cannot demand the physical DNI when the guest brings MiDNI. RD 255/2025 gives the digital version the same legal effect as the physical document for identification, and says so expressly for dealings with the private sector, accommodations included. On top of that, the twelve-month window the decree gave entities to adapt closed on 2 April 2026, so there is nothing left to invoke.

Does MiDNI change the data the guest report requires? No, MiDNI does not change the data the guest report requires: the RD 933/2021 fields are the same. What changes is how identity is verified at the desk, not what is reported to SES.HOSPEDAJES.

Can I keep a screenshot of the guest’s DNI from MiDNI? Keeping a screenshot of the guest’s DNI from MiDNI serves no purpose. The QR expires in seconds and the data isn’t stored on the verifier’s device: a screenshot is useless as live proof. What you do need to do is enter the fields RD 933/2021 requires into the report, just as with any other document.

Do foreign guests use MiDNI? No, foreign guests do not use MiDNI: it is the digital version of the Spanish DNI. They keep identifying themselves with their passport or national ID card, as before.

What if the guest hasn’t activated MiDNI? If the guest hasn’t activated MiDNI, nothing happens: the physical DNI is still just as valid. MiDNI is one more option for the guest, not an obligation on them. The obligation is yours: to accept it when they present it.

What about minors travelling in the group? For minors travelling in the group, MiDNI doesn’t change the report rules: RD 933/2021 still requires registering them and, depending on age, capturing the responsible adult’s details. If the minor has a DNI, they can show it through MiDNI like any other guest; if not, they identify themselves as before. There is detail in how to register minors in the guest report.

Do I need a special reader for the QR? No, you don’t need a special reader for the QR: it is verified from another phone running the MiDNI app or from the official verifier on its website. No extra hardware is needed at reception beyond a device with a camera and a connection, because the check runs in real time.

With digital check-in, MiDNI means nothing to rebuild

If your check-in is digital, MiDNI arrives with your homework done: guests enter their data before arriving, the system validates it against the RD 933/2021 rules, and the report goes out on its own. That is how RegistroViajero works.

The document at the desk, plastic or on a phone, becomes what it always should have been: a seconds-long check.