Registering Minors in Spain: Guest Report Rules by Age

A family with children walks into the apartment, and the same questions come up every time.

Do we register the baby? What data do I ask from a 15-year-old travelling with their parents? Does a minor need a DNI? And what’s that “relationship” field on the form?

Royal Decree 933/2021 has specific rules for minors. They aim to keep the register compliant without asking the impossible of a three-year-old. Here they are, case by case.

The general rule: three age brackets

This gradation comes from the technical specifications the Ministry publishes for the SES.HOSPEDAJES platform. In practice, compliance software has to request different data depending on the guest’s age.

Spain guest registration: children under 14 exempt

Children under 14 do not need an individual guest report. That doesn’t make them invisible to the system: they still count toward the total number of occupied spaces in the reservation. But no ID, address, phone number, or signature is requested for them.

The reservation holder indicates that they are travelling with them, and the accommodation records the correct total occupancy for the night. That’s all.

What about babies? Do I have to register a baby?

No. The exemption covers ages 0 to 13 inclusive. A three-month-old baby counts as a companion, the same as a ten-year-old.

Why the exemption?

Two solid reasons:

1. Many minors don’t have a DNI until they turn 14. Asking a baby or a 5-year-old for an official document makes no sense.
2. Minors travel under the responsibility of an adult who is already identified and registered. Public-safety oversight of the group runs through that adult.

Ages 14 to 17: full registration plus parentesco

Teenagers aged 14 to 17 do get registered like any adult, save for one detail: the relationship (parentesco) to an accompanying adult on the same reservation must be declared.

This is where most mistakes happen.

Which documents are accepted?

In Spain, the DNI is mandatory from age 14, so the vast majority of Spanish minors in this bracket have one and register with it.

The values the Ministry accepts:

• DNI (also requires the support number: the identifier that appears on the back of the DNI below the IDESP code).
• NIE (foreign resident ID for foreigners with residence in Spain aged 14+).
• Passport (common for foreign travellers in this age group).
• ID document from the country of origin, if it’s a recognised official document.

If the minor has a DNI or NIE, the second surname must also be entered.

SES.HOSPEDAJES minor without ID document: what to do

Real case: a foreign 15-year-old without an individual passport, travelling with a family book or a national ID document.

Options, in order of preference:

1. Passport if they have one, even if the minor hasn’t turned 14 in their country.
2. National ID document from the country of origin, if it’s an official individual ID.
3. If no individual document exists, document the case within the reservation by linking the minor to the accompanying adult’s document and declaring the relationship. For edge cases, check with the competent authority.

The family book (libro de familia) is not a personal ID for the minor. It proves a family relationship; it doesn’t identify anyone.

What is the relationship field?

It’s the family or guardianship relationship between the minor and the accompanying adult. The values supported by SES.HOSPEDAJES include:

• Father / Mother
• Guardian
• Grandfather / Grandmother
• Uncle / Aunt
• Brother / Sister
• Other

The check-in form must allow one of these to be selected and linked to the specific adult acting as companion. It’s not enough to say “travelling with an adult”; you have to say which one.

A 16-year-old with their own DNI: is parentesco still required?

Yes. As long as the guest is a minor (until the day before they turn 18), declaring the relationship is mandatory. It doesn’t matter that the teenager has their own DNI and travels without their direct parents: you still indicate the relationship to the adult on the same reservation.

What if they travel without a direct relative?

Typical cases: school trips, summer camps, youth sports teams. The companion is usually the monitor, teacher, or group leader acting as a temporary guardian. The declared relationship is “guardian” or “other” depending on the documentation provided.

If the minor travels alone (uncommon in this age bracket but not impossible), consult the competent authority. Admission of unaccompanied minors to tourist accommodations is generally subject to explicit parental authorisation and may raise concerns from the accommodation, regardless of the registration regulations.

From age 18: standard regime

From the age of majority, registration is identical to that of any adult. No relationship is declared and there’s no mandatory companion. Data is collected in full, and the signer of the accuracy declaration is the guest themselves.

The case of “Guest 1” (the reservation holder)

The first registered guest of each reservation is, by convention, the reservation holder: the person who contracts the accommodation and bears primary responsibility for the rest of the guests’ data being correct.

In practice, the holder is always of legal age. Minors never appear as holders.

Common mistakes when registering minors in Spanish vacation rentals

After processing thousands of check-ins, these are the ones that come up most.

1. Registering a minor under 14 as an adult

Out of habit, some operators fill out a report for each person on the reservation, young children included. It isn’t necessary, and it can trigger rejections from the Ministry if the DNI data is invalid (because the child has none).

Fix: mark the minor as a companion and let the system count them toward total occupancy without requesting a document.

2. Forgetting parentesco for ages 14 to 17

If a teenager is registered without declaring a relationship to an adult on the same reservation, the Ministry returns a validation error and the communication is not considered complete.

Fix: the form should force the selection of a relationship when the guest’s date of birth falls in this bracket.

3. Confusing DNI and support number

The support number is an additional identifier on the Spanish DNI (alphanumeric format like “AAA123456”). It’s different from the DNI number, and it’s required when the document type is DNI.

Fix: the form should ask for it explicitly, with a visual example of where it appears on the document.

4. Second surname missing on DNI/NIE

Spanish documents always have two surnames. If the form doesn’t require it and you submit with one, the Ministry’s validation fails.

Fix: the “second surname” field should be mandatory whenever the document type is DNI or NIE.

Data protection and minors

This is the part that gets overlooked most. GDPR and the Spanish LOPDGDD give minors’ data enhanced protection.

The legal basis for processing in guest registration is compliance with a legal obligation (RD 933/2021), not consent. Even so, four practices are worth keeping:

• Don’t collect more data than the Ministry requires (data minimisation).
• Delete or anonymise once the 3-year retention window the rule sets has passed.
• Restrict access to personal data to authorised accommodation staff.
• Have the accompanying adult, not the minor, sign the accuracy declaration about a minor’s data.

How RegistroViajero handles this

At RegistroViajero the minor registration flow comes ready out of the box:

• Automatic detection by age. The form detects whether the guest is under 14, between 14 and 17, or an adult, and adapts the required fields in real time.
• Relationship required when applicable, linked to the specific accompanying adult on the reservation.
• Chained validations. If you choose DNI, it asks for the second surname and the support number. If you choose passport, it doesn’t.
• Companion’s signature for minors, with the corresponding accuracy declaration.
• Configurable retention in line with GDPR and RD 933/2021. Automatic deletion after 3 years by default.

You can get more context in what RD 933/2021 requires, how to automate guest registration when family groups repeat, the penalties provided for by the law, and how to obtain SES.HOSPEDAJES credentials.

If you manage an accommodation with high family turnover, creating a free account lets you try the full flow for 15 days without a credit card.

This article is informational. For specific cases (unaccompanied minors, judicial guardianship, emergency accommodation, etc.), consult your legal advisor or the competent authority.