A certified email service combines the speed, convenience, and simplicity of email with the legal security provided by registered mail. It is, without a doubt, a highly useful tool for any company or professional who wants to benefit from the reliability, traceability, and efficiency that digital communication can offer.
In this article, we explain what it is, what advantages it brings, how to send one, and the legal framework that supports its validity across Europe. You will also discover how certified email works within the new European context (REM, eIDAS 2) and how Signaturit helps you send legally reliable communications with ease.
Quick definition—A certified email is a secure digital message that provides legally valid proof of sending, delivery, and content integrity. In Europe, it functions as an electronic registered delivery service under eIDAS, offering full legal validity for business and official communications. With providers like Signaturit, certified emails guarantee traceability, timestamps, and authentication, making them a reliable alternative to traditional registered mail.
What is a certified email?
A certified email is a type of email communication designed to guarantee the integrity, authenticity, and traceability of the information exchanged. Thanks to this level of assurance, it can replace more traditional systems such as registered postal mail.
To send certified emails, three parties intervene:
- The sender: the person or entity sending the communication.
- The recipient: the person receiving the information.
- A trusted third party: a certification service provider, such as Signaturit, which generates the evidence that proves the communication took place.
It produces reliable and legally admissible proof of:
- Successful electronic transmission
- Receipt by the recipient
- Integrity of the message and attachments
- Exact dates and times of sending and delivery
- Identity (and IP addresses) of both sender and recipient
How certified email works in Europe: From PEC to REM and eIDAS
In Europe, certified email is governed under the framework of eIDAS, the EU regulation that standardizes trust services and ensures secure electronic interactions across member states.
Traditionally, countries like Italy, Germany, or Switzerland used national systems such as PEC (Posta Elettronica Certificata). To unify these systems, the EU is transitioning from PEC to REM (Registered Electronic Mail)—a new standard designed to ensure interoperability and cross‑border legal validity.
REM elevates certified email to a “Qualified Electronic Registered Delivery Service”, meaning:
- Stronger identification of the mailbox holder
- Interoperability across all EU countries
- Compliance with eIDAS 2
- A single European standard for legally valid electronic communications
Advantages of certified electronic mails
Speed
Sending a certified email is as fast as sending a traditional email.
Ease of use
Tools for secure email are simple and require no advanced technical knowledge. If you can send a standard email, you can send a certified one.
Cost savings
It significantly reduces the cost of sending legally valid communications compared with certified postal letters.
Companies using Signaturit’s certified emails save up to 87% in shipping costs.
Legal validity
It has full legal validity when issued by an accredited trust service provider like Signaturit. The evidence generated allows companies to demonstrate that a communication was sent, received, and remained unaltered.
Under eIDAS, it falls within the category of electronic registered delivery services, which have recognized legal effect throughout the EU.
Article 43 of eIDAS establishes that “data sent and received through an electronic registered delivery service must not be denied legal effect or admissibility as evidence solely because it is in electronic form.”
With eIDAS 2, valid certified email gains even greater robustness in identification, integrity, and cross-border use.
Environmental benefits
Replacing certified letters with certified emails reduces paper and ink consumption and avoids emissions associated with transport.
With Signaturit, we can send certified emails quickly and easily, at a lower cost than the traditional system.
Ricardo Torres. Partner of [A]CODE Abogados.
Certified email vs. Registered email (postal)
Although both methods aim to provide legal certainty, certified email offers several advantages:
| Registered Letter | Certified Email |
| Requires physical delivery | Fully digital |
| Higher costs | Lower costs |
| Longer delivery times | Immediate delivery |
| Risk of loss or damage | Digital custody and integrity |
| Not always automated | Full traceability and timestamps |
Certified email is therefore faster, more efficient, more cost‑effective, and easier to integrate into digital workflows.
How to send certified emails?
Sending a certified email is straightforward. Although steps can vary depending on the provider, the process usually involves:
In any case, there are only a few steps needed:
- Accessing a certified email platform
- Entering the recipient’s email address
- Writing the message and attaching documents
- Sending it through the certified channel
On Signaturit’s platform, this same process is simplified and intuitive. Additionally, if your company already uses management or business software, Signaturit’s API allows seamless integration, so you can send certified emails directly from your existing tools.
You can also see the process in action in this video.
When to use certified email: common use cases
It is especially useful for communications that require proof of delivery, such as:
- Contract notices and termination letters
- Debt collection communications
- HR notifications (contracts, payroll, schedule updates)
- Legal notices and claims
- Financial and insurance documentation
- Delivery of invoices or unpaid bills
- Authorization requests
- Customer notifications with legal impact
Its reliability makes it an essential tool across industries such as legal services, real estate, finance, insurance, etc.
Free certified emails
While certified email is more cost‑effective than traditional alternatives, it requires:
- A certified provider,
- a digital platform,
- and trusted evidence generation.
For this reason, it is not a completely free service. However, Signaturit offers a free trial so you can experience the benefits without commitment, including access to both certified email and our electronic signature solution.
Certified email in the United States: key differences
While Europe relies on eIDAS and is moving toward a unified REM standard, the United States follows a different model. There is no government standard for certified email similar to PEC or REM. Instead, American companies use private certified email providers that generate legally admissible proof of sending, delivery, and content.
One of the most established solutions is Registered Email™ (RMail), which has been used across the U.S. for more than two decades. It produces a Registered Receipt™, a digital record accepted as court‑admissible evidence in all 50 states.
These services are widely used in industries such as insurance, legal services, HR, and finance, where reliable documentation is essential. The U.S. legal framework relies primarily on:
- ESIGN Act (Electronic Signatures in Global and National Commerce Act)
- UETA (Uniform Electronic Transactions Act)
Both establish that electronic records and signatures have the same legal effect as paper documents when integrity, authentication, and retention requirements are met.
This means certified email can be just as legally binding as USPS Certified Mail, provided the provider complies with these digital evidence standards.
While the purpose is similar to Europe, providing traceable, provable communication, the U.S. ecosystem is more flexible, decentralized, and driven by private certification rather than a unified federal standard.
Conclusion
Certified email is an essential tool for digitizing communications with full legal security.
It offers companies:
- Lower costs,
- greater speed,
- environmental benefits,
- and legally admissible evidence.
With European REM standards and eIDAS 2, certified email becomes even more important for ensuring secure, interoperable, and legally robust communications across the EU.
At an affordable cost and with no technical complexity, your company can simplify correspondence, increase efficiency, and maintain maximum legal certainty.
