New Real Estate Advertising Law: mandatory documents to advertise your flat
The real estate market takes a historic step towards transparency. With the recent entry into force of Law 10/2025, owners can no longer publish an advertisement without first having all the property's legal documentation in order. Discover what information is now absolutely mandatory, such as the Certificate of Occupancy or the Energy Performance Certificate, and how these strict regulations protect the rights of buyers and tenants.
10/2025Law in force
RequiredEnergy Performance Certificate and Certificate of Occupancy
100%Transparency from day 1
SevereBreach of contract
In this article
What is Law 10/2025 and who does it affect?
Law 10/2025, focused on customer service, strictly regulates the information advertisers display on real estate portals, social media, and physical advertisements. It directly affects property owners, developers, real estate agencies, and any professional intermediary.
The purpose of this regulation is to protect the end consumer by ensuring that the property they are viewing meets all legal requirements to be sold or rented, preventing fraud or last-minute surprises.
Full transparency on the legal status of the property
Until now, it was common to see ads for homes that were actually commercial premises without a certificate of occupancy, or apartments whose energy performance certificate was obtained at the last minute. The new law strictly prohibits this practice.
"With the new regulation, an advertisement can no longer rely solely on pretty pictures. The law requires the property to have its Certificate of Occupancy and Energy Performance Certificate from minute one, with no excuses or delays."
— Expert Legal Analysis, 2026This means that it is an unavoidable obligation for the owner to have all documents up to date before uploading the advertisement to any real estate portal or entrusting its commercialization to an agency.
Rental listings: stressed areas and Certificate of Occupancy
In the rental market, the legal analysis of the new regulation is especially strict:
- Reference to stressed areas: if the property is in a high-demand residential area (such as Barcelona), the advertisement must explicitly mention this condition and display the applicable rent control index.
- Current occupancy certificate: The advertisement must guarantee that the property is legally a dwelling. This measure seeks to put an end to the fraudulent rental of offices, studios, or commercial premises by passing them off as apartments.
- Energy Performance Certificate: the exact letter of the energy consumption and emissions must be stated, allowing the tenant to calculate the actual utility costs for the apartment.
Sales listings: the end of "Certificate in progress"
In the case of buying and selling, owners and developers have also had to adapt all their publications to comply with the law:
What documentation you should prepare before listing your apartment in 2026
- Energy Performance Certificate (EPC): It is mandatory for the energy efficiency label (A to G) to be visible in the advertisement. The typical phrase "certificate in progress" is no longer legally valid and may result in a penalty.
- Legal Transparency: the advertisement should make it clear that the property has a valid Certificate of Habitability.
- Urbanistic Conditions: mandatory mention if the property is government-subsidized housing (VPO) or has any special urban planning restrictions.
Frequently Asked Questions (FAQ)
Does this law affect a private landlord who advertises their own flat?
Yes. Although Law 10/2025 is aimed at improving consumer services, platforms such as Idealista apply the mandatory energy certificate and truthful information regulations to all users, whether individuals or companies.
What happens if I advertise my flat without an Energy Performance Certificate?
It is considered a serious offense. Real estate portals may block or remove your listing, and you risk financial penalties from consumer or housing authorities.
Can I put "ID in process" while I wait for it to be granted?
It is not advisable. The law requires full transparency from the outset. Advertising a flat as a dwelling without official confirmation (Certificate of Occupancy) is considered misleading advertising.
How do I know if my rental property is in a stressed area?
In the case of Catalonia, you can consult it through the portal serpavi.mivau.gob.esBy law, the advertisement must explicitly state this condition in its text or through a visible tag, providing the value of the applicable reference index.
Do you want to rent or sell your apartment in full compliance with the law?
At All4Flat, we handle your Certificate of Occupancy and Energy Performance Certificate. We publish your listings in strict compliance with current regulations so you don't have to worry about a thing.
Contact our advisors
