Achieving SMS Compliance Spain is now a top priority for international brands. If your business sends alphanumeric messages to the Spanish market (+34), you must adapt to a new regulatory framework.

According to Order TDF/149/2025, the Spanish National Regulatory Authority (CNMC) has mandated that every Alphanumeric Sender ID must be registered. To ensure your SMS Compliance Spain, your brand names must be verified in the national database by 7 June 2026. Messages from unregistered aliases will be blocked by local operators, with no exceptions.

After this date, any SMS, MMS, or RCS message sent to a Spanish mobile number using an unregistered alias will be summarily blocked by local network operators. There will be no grace period beyond this date

This shift in SMS Compliance Spain is part of a European-wide effort to combat smishing (SMS phishing). By creating a verified SMS Sender ID registration system, authorities ensure only legitimate owners can use specific brand names.

As a licensed Tier-1 operator in Spain, Lleida.net is managing the SMS compliance transition for our international partners to ensure zero service interruption.

This guide breaks down exactly how international senders must register their SMS aliases with the CNMC.

Key Requirements for SMS Compliance Spain

The CNMC Alias Registry (regulated under Circular 1/2026 serves as the official clearinghouse for all alphanumeric traffic. Understanding the registry's rules is the first step toward SMS Compliance Spain. It provides the legal framework for the security requirements set out in Order TDF/149/2025.

What is an SMS Sender ID?

A Sender ID is the alphanumeric string (e.g., LLEIDA.NET, HMRC, or ROYAL-MAIL) that identifies your brand. To maintain your SMS Compliance Spain, these names can no longer be used freely without prior validation.

Until now, any business could use virtually any name as a sender, a loophole frequently exploited by scammers to impersonate trusted brands. The new SMS Registry shuts this door: if a Sender ID is not registered and verified, the message will be blocked at the gateway.

Does this apply to your business?

Yes. To ensure full SMS Compliance Spain, any business sending messages to Spanish mobile numbers (+34) must register their aliases to ensure SMS Compliance Spain., regardless of their company’s headquarters.

To maintain SMS Compliance Spain, you have three paths for registration:

• The Sender ID owner (company or public body)
• The Registered Originating Provider (ROP) on their behalf
• An expressly authorised third party

To maintain SMS Compliance Spain, registration is mandatory for these services:

• Standard & Registered SMS, RCS
• Click & Sign (E-signature)
• Openum
• Tailored SMS workflows.

All custom SMS Sender IDs must be CNMC-registered, regardless of the platform you use.

Registration Roadmap: 3 Steps to Comply

To guarantee your SMS Compliance Spain, follow this technical process:

1. Audit your IDs: Identify every alphanumeric sender you use for the +34 market.
2. Log in to the CNMC E-Office: is managed through the CNMC’s electronic office. The process requires authentication via digital certificate or the Cl@ve system, and for your convenience, multiple aliases can be registered within a single application.

3. Await Approval: The maximum processing time is one month.

Need help? Our team is available to support you throughout the process.

Step-by-Step: The Filing Process

To secure your SMS Compliance Spain, applicants (whether the owner or an authorised third party) must provide the following details in the form:

• The Sender ID to be registered
• Proof of legitimate link to the owner
• Owner’s details and activation date
• Expected end date (optional)
• Third-party details (ROP or other authorised entity), if applicable

If the applicant is not the owner, the CNMC will require the owner to expressly confirm authorisation within 10 working days.

Step-by-Step Guide: CNMC Portal

The critical distinction is between the Sender ID owner and the filer, as this dictates the specific workflow and timelines.

Registering your SMS Sender ID as a Lleida.net client:

• Access the CNMC E-Office: Log in using a digital certificate or the Cl@ve system.
• Select Applicant Type: Choose "On own behalf" and enter your credentials (NIF/Tax ID, name, company, email, address, and phone).
• Select Submission Type: Choose "Sender ID Registration"
• Legal Representative: Enter the details for the owner’s authorised signatory.
• Configure your Alias: Set the name, activation date, and upload your Proof of Authority (legitimate link documentation). Finally, select your provider; if you are a Lleida.net client, we are listed as an available originating provider in the dropdown menu.

Need help with your registration? Contact the support desk at: [email protected]

What about your existing Sender IDs?

To guarantee a seamless transition, the regulation allows Registered Providers to perform a one-time bulk migration of all active IDs. Lleida.net will handle this filing automatically for our clients.

If you would like your IDs included in this priority upload, please submit your details via our portal by 26 April 2026.

When does the mandatory blocking of unregistered Sender IDs begin?

The enforcement of these blocking obligations officially kicks in on 7 June 2026. Until 6 June, providers will have access to a dedicated testing environment to recalibrate their systems and finalise the SMS Sender ID registration for all active IDs.

Beyond the Registry: Real-Time Verification

The new SMS database is just one pillar of a major anti-fraud offensive led by the Spanish Ministry for Digital Transformation. To add a second layer of defence, the CNMC is launching a Public Lookup Portal. This "transparency hub" will allow businesses and consumers to verify Sender ID ownership on the fly, making it significantly harder for scammers to operate under the radar.

Do you use alphanumeric senders for your SMS campaigns in Spain? You must take action now to ensure your SMS Compliance Spain is up-to-date. Contact us today if you require assistance or further information.

Contact Lleida.net Support

Source: CNMC (National Markets and Competition Commission, Spain)

Rental extension Spain is a key option if you need to extend your rental contract under current regulations.

If you need to send a registered notice to your landlord in Spain to request a rental extension of up to two more years, here’s how to do it in under 5 minutes for just €1 using Lleida.net’s Registered email service.

Royal Decree Law 8/2026, in force since 22 March 2026 and pending approval by Parliament within 30 days, allows certain rental agreements in Spain to be extended for up to two additional years, under the same conditions and with rent increases capped at 2% per year.

Under this regulation, the extension is not automatic. You must formally request it through a channel that provides proof of the sending date, the content of the message and confirmation of delivery.

Keep reading to see how simple it is to send a registered notice to your landlord from any device. This rental extension Spain process can be completed quickly if you follow the correct steps.

Rental extension in Spain: what is Royal Decree Law 8/2026

Royal Decree Law 8 2026, introduces urgent housing measures in Spain to mitigate the economic impact of the situation linked to the conflict in Iran.

Among these measures, it allows the extension of primary residence rental contracts for up to two additional years, while limiting rent updates to a maximum of 2%.

This applies if all the following conditions are met:

• Your rental agreement is for your main home and was active when the regulation came into effect
• The contract is governed by the Spanish Urban Lease Act (LAU 1994)
• The rental agreement expires before 31 December 2027

If your situation meets these criteria, you can request an extension of up to 2 additional years, in yearly increments, while maintaining the same conditions as your current contract.

Rental extension Spain: why a Registered email is required

This is where many tenants make mistakes.

It is strongly recommended to submit your request through a channel that can certify three key elements:

• The date the request was sent
• The exact content of the message
• The date it was delivered to the recipient

This rules out standard email, phone calls and instant messaging apps.

In Spain, the method that meets these legal requirements is the registered notice. Today, you can send its digital equivalent online from your computer or mobile, without visiting a post office.

Notify your landlord in Spain legally: what most tenants do wrong

Many tenants try to extend a rental contract in Spain using email or messaging apps.

The problem is simple.

These methods do not generate legal proof.

If you want to notify your landlord in Spain legally, you need a method that certifies the message, the content and the delivery.

Rental extension in Spain: how to send a Registered email to your landlord

There is nothing to install. Lleida.net’s registered email service works directly from your usual email account, whether you use Gmail, Outlook or any other provider.

Just follow these steps:

1. Make sure your email address is registered in the user portal (Tools section, certified email > how to send > step 2 .

2. Write your message and attach any necessary documents. Draft the email addressed to your landlord.

3. Add your landlord’s email address.
Enter their email in the “To” field.

4.In the CC field, add: [email protected].
This is the step that converts your standard email into a registered message with full legal validity.

5. Get your documentary evidence

Within minutes, you will receive a certificate confirming the sending date, the full content of the message and the delivery to the recipient’s server. Keep it safe, as this is the document you will need if you have to prove that your request was made on time.

This certificate has the same evidential value as a registered notice, with the advantage that it is generated in minutes, from any device and for €1.

If the decree is ultimately not approved by Parliament, this certificate may become your key piece of evidence to support a legal claim.

Following these steps ensures your rental extension Spain request is properly documented and valid.

Want to see how it works

If you would like to see the process step by step, watch the video below.

Using an electronic Burofax in rental agreements has become a standard practice for both tenants and landlords in Spain. If you need to establish a legal record of communication between parties in rental agreements, it is a fast, cost-effective, and legally binding solution to provide conclusive evidence

Note for international users: In the Spanish legal system, a Burofax is a specialised service used to send documents where the sender requires proof of delivery and, crucially, certification of the contents. While traditionally sent via the post office, the electronic Burofax (Registered email) in rental agreements offers the same legal weight with much greater efficiency.

Unlike a standard registered letter, an electronic Burofax in a rental agreement allows you to prove who sent the communication, when it was sent, and exactly what it contained, all within minutes and without the need for physical paperwork.

Whether you are a tenant or a landlord managing rental agreements, using an electronic burofax is essential to ensure legal protection and traceability.

In this guide, we explain how to send an electronic Burofax in under 5 minutes, with full legal validity, starting from just €1.

What is an electronic Burofax in rental agreements, and what makes it legally valid?

An electronic Burofax is an email certified by a Qualified Trust Service Provider. When you send it, Lleida.net monitors the communication in a secure, audited environment under its exclusive control. As a result, a certificate is generated containing all delivery details, serving as private evidence with full legal standing.

The certificate includes:

• Sender’s legal name, ID, and email address.
• Recipient’s email address.
• Date and time of sending and delivery to the recipient's server.
• Status of the recipient's mail server.
• The full content of the email and its attachments.
• Technical Annex: Message ID, outgoing server IP, and destination server IP.

The electronic Burofax in rental agreements is a reliable communication mechanism that generates legal certainty for both parties in a rental agreement.

Why does it have legal validity?

With over three decades of industry expertise, Lleida.net is a Qualified Trust Service Provider under EU standards. This status guarantees that our certificates carry full legal weight and are universally recognized across all European Union member states

The legal framework supporting this service is robust:

• eIDAS Regulation: The European standard regulating certified electronic communications. It stipulates that data sent via a certified delivery service cannot be denied legal effect or admissibility in court solely because it is in electronic form.
• Spanish Law: Law 6/2020 on Trust Services and the Civil Procedure Law (LEC) recognize electronic documents as both evidence and official notification. Furthermore, Article 24 of the LSSICE admits them as documentary evidence in the formation and certification of electronic contracts.
• Consolidated Jurisprudence: Numerous court rulings lately have expressly recognized the evidentiary value of certificates issued by Lleida.net in civil and commercial proceedings.

Traditional Burofax vs. Electronic Burofax: A comparison

To choose the right tool for your rental agreement, it's essential to understand the shift from legacy postal Burofax to its digital counterpart. Both are legally admissible, but their operational workflows and costs, are worlds apart:

When to use electronic Burofax in rental agreements as a tenant

As a tenant, an electronic Burofax provides irrefutable proof that you sent a formal notice on a specific date. This documented evidence is often the deciding factor should a dispute with your landlord arise late

Common use cases for tenants:

• Requesting a formal lease extension: If your contract is nearing its expiration, and you wish to renew, a Burofax provides irrefutable evidence of your request, ensuring your intent is legally documented.t.
• Notice of non-renewal: (Moving out): When terminating a lease, you must adhere to strict legal notice periods. An electronic Burofax serves as certified proof that you notified your landlord within the required timeframe.
• Claiming a security deposit refund: If a landlord withholds your deposit without justification, sending a formal Burofax is the standard legal precursor to any court claim or mediation.
• Reporting damages or required repairs: Documenting property damages via Burofax creates an official, time-stamped record. This protects your liability and proves you fulfilled your duty to inform the owner if the situation escalates.

For a tenant, an electronic Burofax is a high-value, low-cost investment. Starting at just €1, it generates a certified legal document that can save you thousands in potential legal fees or lost deposits.

When to use electronic Burofax in rental agreements as a landlord

Registered communication is not just for tenants. Landlords can also leverage this service to document official notices with full legal guarantees, maintaining the same speed and low cost.

Common use cases for landlords:

• Notice of non-renewal: (Lease termination): Notify the tenant within the mandatory timeframe established by the Spanish Urban Leasing Law (LAU). A Burofax ensures you have certified proof of both the notification date and the specific content of the notice.
• Documenting the property's condition:Create an official, time-stamped record of a property's state. This is vital evidence if disputes arise regarding damages or "wear and tear" at the end of the tenancy.
• Claiming unpaid rent(Arrears): Prove that you have formally requested payment within the legally required periods. This is a mandatory step before initiating any eviction or debt recovery proceedings.
• Notifying works or property maintenance: Ensure the tenant is officially informed of upcoming repairs or inspections with a certified delivery timestamp, preventing claims of "unauthorized entry."
• Denying lease assignment or subrogation: If a tenant requests to transfer the contract to a third party, and you decline, a Burofax leaves no room for ambiguity regarding your legal position and refusal.

For landlords, the electronic Burofax provides the same legal safeguards as it does for tenants in rental agreements: it serves as certified proof of your communication’s content and delivery date

How to send an electronic Burofax in minutes: Step-by-step

The process is as simple as sending a regular email.

1. Sign up at Lleida.net (it’s free and only required once)
2. Purchase credits. Sending a registered email costs 7 credits
3. Access MyCloud. In the “Tools” section, you’ll find guides and videos explaining how to send it.
4. Compose your email using your usual email provider (Gmail, Outlook, etc.).
5. Add our certification address in the CC (Carbon Copy) field: [email protected]
6. Send the email. You will receive your documentary evidence in your inbox. You can also download it from your back office. This document contains all certified data: date, time, sender, recipient, content, and attachments.

It works with Gmail, Outlook, Apple Mail, or any other client. The entire process takes less than 5 minutes and costs from €1.