Certified SMS, messages with legal validity

What is a Certified SMS?

A Certified SMS is a standard text message delivered to the recipient’s mobile phone, but it includes a certification process that grants it legal validity. This process guarantees authenticity, integrity, and secure delivery. Unlike regular SMS, a Certified SMS is sent through a trusted provider (Qualified Trust Service Provider) that accurately records its delivery. This means digital evidence is preserved, such as dates, content, sender, and every event of sending and receiving.

In practice, a Certified SMS works like a “registered letter” or “digital burofax.” It contains the text to be notified, and once sent, a digitally signed PDF receipt is generated that verifies the content, the exact date, and the time of delivery and reception.

Differences Between a Standard SMS and a Certified SMS

The key differences between a traditional SMS and a Certified SMS with legal validity lie in the sender’s identification and the proof of delivery. A standard SMS can be sent by anyone without any special accreditation. The recipient sees the text, but there’s no guarantee of who sent it or when it was actually received. In contrast, a Certified SMS includes verified sender details, such as a registered sender ID, and automatically generates a digitally signed certificate with date and time stamps.

In short, the main difference is legal validity. A Certified SMS generates a document that can be used as evidence in court—something a standard SMS cannot provide. If a dispute arises, the certificate associated with the SMS will serve as legally binding proof of the company’s version, unlike an ordinary SMS, which lacks this evidentiary support.

How a Certified SMS is Sent and Received

Sending a Certified SMS with legal validity follows steps very similar to a regular SMS, but with an added certification process. From the sender’s perspective, the action is simple: a message is sent from a platform (web or API) to the recipient’s mobile number. The recipient sees it as a normal text message.

The major difference takes place in the back-end of the certifying platform, which records every critical event. For example, it logs the exact date and time the message was launched, confirmation of delivery to the mobile operator, receipt on the final device, and even whether the recipient opened it.

Once the recipient receives and opens the message, the system automatically generates a proof document (usually a PDF) containing all the process details. This document is then sent to the sender as legal evidence.

Advantages of Using Certified SMS

Certified SMS combines the speed of instant messaging with reinforced legal guarantees. Its main benefits include:

If you’d like to start taking advantage of these benefits, you can try platforms such as LabsMobile, a service specialized in sending Certified SMS with full legal validity and compliance with eIDAS regulations.

Security and Reliability in Communication

By including an electronic signature and timestamp, Certified SMS ensures the authenticity of the sender and the integrity of the content. This prevents impersonation or message tampering. In practice, the sender can be certain that only they could have sent that specific message. At the same time, the recipient can verify the message source—such as a verified business sender—boosting mutual trust.

Message Tracking and Traceability

Every Certified SMS leaves a complete audit trail. The platform keeps a detailed record with the exact time and date of sending, confirmation of delivery to the operator, and, when available, confirmation of reading by the recipient. Network metadata and sender details are also logged.

Thanks to this certification process, traceability ensures that the entire communication can be reconstructed at any time. In case of disputes, these records can be accessed on the platform and presented as evidence.

Time and Cost Savings Compared to Traditional Methods

Unlike traditional notifications such as registered letters or burofax, Certified SMS is delivered in seconds. There’s no need to print or send by postal mail. The process is fully online, drastically cutting down on administrative time.

In terms of cost, it is much more affordable. A Certified SMS typically costs just a fraction of a burofax or registered letter. This represents significant savings for companies handling frequent or large-scale notifications. Being a digital process, it also eliminates paper, ink, and postage expenses—making it eco-friendly as well.

Altogether, Certified SMS combines operational efficiency (speed, scalability, lower costs) with legal guarantees (official record, digital signature), offering a secure, convenient, and low-cost communication solution.

Legal Validity of Certified SMS

Certified SMS with legal validity have full legal recognition and are acknowledged as legitimate means of communication. They carry the same legal weight as traditional formal channels. In many jurisdictions, a Certified SMS can be presented as evidence in court or administrative proceedings. In fact, within the European Union they are considered “reliable notifications” when issued by a Qualified Trust Service Provider (QTSP).

In Europe, the eIDAS Regulation recognizes Certified SMS providers as QTSPs authorized to issue communications with evidentiary value. This means an SMS sent by a QTSP is legally supported by an electronic seal admitted under the regulation.

Moreover, Certified SMS are typically accompanied by a digital certificate securely stored for years, as required by law. Regulations state that the provider must retain this proof for future reference. In legal and administrative practice, a Certified SMS with legal validity is considered reliable and enforceable evidence, provided it is issued by a qualified provider.

Legal Recognition Across Jurisdictions

The legal validity of Certified SMS is not limited to a single country—it is widely recognized internationally. In the European Union, as mentioned, the eIDAS regulation allows Certified SMS issued by a QTSP to be considered valid for official communications. This applies not only to Spain but to other EU member states as well.

In Latin America and the United States, certified communications are increasingly accepted as evidence, often under the same logic applied to burofax or certified email. For example, rulings in Spain have confirmed that Certified SMS is equivalent in effectiveness to any other reliable written notification.

The general rule is that a Certified SMS can be used with full legal validity wherever local regulations recognize trustworthy electronic communications. To maximize validity, it’s essential to use a provider that complies with eIDAS or equivalent national certifications. This ensures the traceability and custody of certificates meet required legal standards.

Common Use Cases Requiring Legal Validity

Certified SMS is particularly useful when it is necessary to formally prove the delivery of a communication. Typical use cases include:

• Judicial or administrative notifications: Summons, rulings, fines, tax sanctions, or any administrative act requiring proof of official notification.
• Debt management and collections: Payment reminders, debt claims, or recovery proceedings where proof of receipt is crucial.
• Employment and HR processes: Notifications to employees regarding contracts, dismissals, changes in employment conditions, or delivery of payslips and sensitive information. For example, confirming proof of dismissal notice.
• Contracts and services: Confirmation of service agreements, policy renewals, changes to terms of service, or affiliations in sectors like banking, telecom, insurance, or utilities.
• Legal sector: Law firms use Certified SMS to communicate with clients (deadlines, court summons, delivery of legal documents). In civil or criminal cases, SMS can serve as an additional valid channel of notification.

In each of these scenarios, Certified SMS with legal validity ensures effective communication.

Comparison with Other Legally Valid Notification Methods

Certified SMS is often compared with methods like burofax, registered postal mail, or certified email. All of these serve the purpose of reliable notification, but Certified SMS offers unique speed and cost advantages. For example, a traditional burofax requires printing, postage, and longer delivery times. Certified SMS, however, arrives instantly on the recipient’s phone, avoiding printing and mailing costs.

Its cost per message is also much lower. Compared to certified email, Certified SMS often achieves higher open rates, since users usually read SMS messages more quickly, without relying on internet access. Unlike non-certified methods (regular mail, uncertified email, WhatsApp, or other apps), Certified SMS provides full legal validity and evidence.

Practical Applications of Certified SMS

Certified SMS with legal validity is already part of the corporate toolkit for many businesses. Being versatile, it integrates into workflows where paper notifications or fax used to be the norm.

Use in Legal and Contractual Notifications

In legal and contractual contexts, its evidentiary value is key. Any formal or contractual notification can be sent via Certified SMS when proof of delivery is required. Its ease of use and legal backing make it a very attractive alternative to traditional paper-based notifications.

Examples of Industries Benefiting from Certified SMS (Banking, Insurance, HR)

Any sector requiring official or sensitive communications benefits from Certified SMS as a faster and more cost-effective solution compared to traditional methods. Public institutions, insurance companies, financial entities, and large HR departments are among the main users, taking advantage of the traceability and security this service offers.

Key sectors include:

• Banking and Finance: Banks and fintechs notify clients of critical operations, payment reminders, or regulatory updates via Certified SMS. They can prove that clients were informed about suspicious transactions, contractual changes, or upcoming payments. Debt collection departments also use it for legally certified reminders.
• Insurance: Insurance companies notify clients of claims, policy renewals, or compensations through Certified SMS. This speeds up claims management, giving clients proof of submission or receipt of compensation documents (e.g., indemnity payments).
• Human Resources: HR departments use it for notifications requiring legal proof: interview calls, hiring or termination notices, labor agreements, or sending payslips and contracts. For example, a dismissal notice sent by Certified SMS ensures legal evidence of delivery.
• Other sectors: Healthcare, education, logistics, or public administration. In healthcare, certified messages may confirm medical appointments or treatment updates. In education, schools can notify parents or students (e.g., absence alerts) with legal proof. In logistics or supply chains, Certified SMS confirms deliveries or reports incidents.

Integration with Existing Business Systems

A major advantage of Certified SMS is easy integration into companies’ digital workflows. It can be embedded into ERP, CRM, or internal applications seamlessly.

Most Certified SMS solutions also provide dashboards to manage campaigns and access generated certificates. This allows legal or compliance teams to download PDF certificates at any time from the provider’s portal.

How to Send a Certified SMS

Sending a Certified SMS with legal validity is as simple as sending a regular SMS, provided you use a specialized platform. The first step is choosing a certified SMS provider. These providers ensure their services meet legal requirements (eIDAS) and simplify the technical process.

One such platform is LabsMobile, which allows Certified SMS to be sent via its web portal or through API integration, fully compliant with eIDAS and with Spanish-speaking technical support.

Here’s the step-by-step process:

1. Setup: The sender logs into the Certified SMS platform (web portal or API). Required fields must be filled in: recipient’s phone number, recipient’s name (optional), message text, and attached documents if necessary. The certified sender ID (e.g., registered company name or SMS number) is also selected.
2. Sending: Once the content is reviewed, the sender clicks “Send” on the platform. The system immediately routes the SMS to the recipient’s mobile operator.
3. Reception: The recipient receives the Certified SMS as a normal text (sometimes with a special identifier to mark it as certified). At this point, the system logs the delivery. If the SMS includes links or attachments, the recipient can open or download them.
4. Certificate generation: Once delivered (and when accessed by the recipient), the platform generates a proof certificate in PDF format. This document contains full details: sender number, recipient number, timestamps of sending and delivery, full message content, operator metadata, and whether it was read. The certificate is digitally signed and timestamped, ensuring legal validity. The provider then delivers the PDF to the sender (via email or portal download). This serves as final legal proof of the Certified SMS.

Certified SMS Service Providers

Several companies specialize in providing Certified SMS with legal validity. Among them, LabsMobile offers services fully compliant with eIDAS and other local notification regulations. They provide online platforms and APIs that automatically generate digitally signed certificates for each message. When choosing a provider, it is essential to ensure they are a QTSP (Qualified Trust Service Provider) so that the SMS is legally recognized.

Steps to Configure and Send a Certified SMS

Specific steps may vary by provider, but the general process is:

1. Account setup: Create an account on the provider’s platform and validate your company’s identity. Legal documents may be required. Configure the certified sender ID (e.g., company name) and prepare SMS templates if needed.
2. API credentials: If integrating via API, the provider supplies credentials (username, password, or API keys) to connect your system. The API endpoint for certified SMS is also provided.
3. Technical integration (optional): For internal systems, a call to the API is programmed with parameters like recipient number, message text, metadata, message lifetime, language, etc., and how the certificate will be received (e.g., callback URL or portal download). LabsMobile provides API documentation to simplify this process.
4. Sending: Once ready, the SMS is sent through the web interface or integrated system. It is delivered like a normal SMS, while the provider manages the secure certification process.
5. Acknowledgment of receipt: Since the SMS is certified, the platform issues an official receipt, including immediate digital confirmation and the final PDF. The sender can check delivery status (delivered, read, pending) and keep the certificate as legal proof.

Technical Considerations and Prerequisites

To ensure the legal validity of Certified SMS and proper functionality, several requirements should be considered:

• Certified provider: Must be a QTSP authorized by the relevant authorities, ensuring compliance with eIDAS (or local equivalent). This includes secure servers, recognized timestamping, and proper certificate storage.
• Verified sender ID: Many platforms require the sender ID (e.g., company name) to be registered and approved, preventing spam and ensuring messages aren’t blocked by operators.
• Message length and format: Certified SMS may allow more characters than regular SMS (some up to 612 characters), but conciseness ensures reliable delivery. Avoid special characters or emojis, as they may affect encoding—plain text is best.
• Regulatory compliance: Content must respect data protection and privacy laws (e.g., not sending sensitive data without consent). Spam and deceptive content are prohibited.
• Technical integration: If using an API, ensure a secure HTTPS environment for requests, proper error handling (e.g., failed SMS), and certificate storage.
• Certificate storage: Certificates must be kept for years, as often required by law. While many providers store a copy in the cloud, companies should also download and archive their PDFs for long-term retention.

From an implementation perspective, these requirements are not overly complex: essentially, choose an accredited provider, configure the sender ID, and follow technical guidelines to ensure every message sent is a Certified SMS with full legal validity.

LabsMobile provides the technology and legal assurance you need to send Certified SMS with legal validity quickly, securely, and traceably. Start optimizing your legal and professional communications today: sign up for free and send your first Certified SMS from our platform.