Electronic registered delivery · Article 43 eIDAS

Certified email with legal validity. Notify in seconds, not days.

Payment demands, employment communications, changes of terms or GDPR responses: every email goes out with proof of sending, delivery, content and time. You receive the evidence certificate as a PDF and it is filed in the case record. No registered post, no queues, nothing for the recipient to install.

No card required eIDAS timestamping Nothing for the recipient to install
Evidence certificate
Delivered
SubjectPayment demand · invoice 2026-0417
Sent29/09/2026 · 09:14:02 UTC
Delivered29/09/2026 · 09:14:05 UTC
Attachmentsinvoice.pdf · demand.pdf
SHA-256 hash9f2c…b7e1
Timestamp
✓ eIDAS
Integrity
✓ Verified
Case record
Filed

Every email generates a PDF of evidence that any third party can verify, even after you stop being a customer.

<5 s
From sending to evidence
Compared with 24–48 h for registered post to be delivered
€8.71
The cheapest online burofax in Spain
Correos 2026 tariff · up to €36.01 with custody and certified copy
0
Steps for the recipient
They receive an ordinary email; no registration, no download
How it works

From sending to a filed certificate in 3 steps

You send it, or the process triggers it. Dokuflex does the rest.

1

You write it, or it writes itself

You write the email with its attachments, or the process composes it from a template (payment demand, employment letter, GDPR response) using the case data. Choose whether the recipient sees the certification notice or whether the email stays discreet.

2

We record and time-stamp every milestone

Dispatch, delivery to the recipient's server, opening and attachment download where the mail client allows it. Every event carries a timestamp from an eIDAS trust service provider and the content is fixed with a SHA-256 hash.

3

You get the certificate and it is filed

An electronically signed PDF of evidence with the full message, the attachments, the events and their hashes. It is stored in the case record of the document management system with its retention period and can be verified without being a customer.

Try it free · no card required
Use cases

Every communication you may one day have to prove

If tomorrow someone could say "it never reached me", today it goes out certified.

Debt collection

Staged payment demands (day 15, 30 and 60) with the invoice attached. The date of a formal, provable demand marks the start of late-payment interest and underpins any court claim.

Employment communications

Dismissal letters, disciplinary sanctions, substantial changes to working conditions, end of fixed-term contracts, formal summonses and payslip delivery. With date and content proven, and a signed acknowledgement if you need one.

Customers and contracts

Price and terms changes, notices of non-renewal, contract terminations, cancellations and warranty communications. Every change with proof that it was communicated on time.

GDPR and compliance

Responses to data subject requests within the one-month deadline, breach notifications to affected individuals, demands to data processors. Links with the GDPR module.

Suppliers and property

Demands for breach, non-conformities, order cancellations, notices to tenants and owners' associations, rent reviews. Without waiting for the postman.

Insurance and finance

Claim communications, declined claims, policy expiry, KYC demands and outstanding documentation. Full traceability for audit and for the regulator.

The proof

What the evidence certificate contains

In court, nobody argues about whether you sent an email. They argue about whether it arrived, exactly what it said and when. The certificate answers all three questions with data an expert can check without asking us for anything.

Data sent and received using a qualified electronic registered delivery service also enjoys the presumption of integrity, of sending by the identified sender, of receipt by the identified addressee and of accuracy of the date and time (Article 43(2) of the eIDAS Regulation).

Request a sample certificate
Element What it proves
Sender and recipientAuthenticated sending account in Dokuflex and destination address exactly as sent.
TimestampingDate and time of every event set by an eIDAS trust service provider, not by your server's clock.
Full contentSubject, body and attachments with their SHA-256 hash: any later change to a single character breaks the fingerprint.
Delivery eventsAcceptance by the destination server, opening and attachment download where the mail client allows it, with the technical log.
Certificate signatureThe PDF is electronically signed; it can be verified with any reader without depending on Dokuflex.
CustodyFiled in the case record with configurable retention and free export. Six years is the prudent reference in Spain (Article 30 of the Commercial Code); other countries have comparable rules.
Comparison

Certified email vs registered post vs ordinary email

Registered-post prices are the Spanish burofax under the Correos 2026 tariff (mainland Spain and the Balearics); comparable services in other countries cost similar amounts.

Criterion Dokuflex certified email Registered post (burofax) Ordinary email
Proof of sending and dateYes, with eIDAS timestampingYesNo (headers can be manipulated)
Proof of contentYes, in full with a hash, attachments includedOnly with content certification (extra cost)No
Proof of deliveryYes, server acceptance and opening where possibleYes, with acknowledgement of receipt (extra cost)No
Time until you have evidenceSeconds24–48 h, longer if the recipient is absentImmediate, but with no evidence
Cost per communicationPer item sent, no lock-in, no page limitFrom €8.71 online and €12.72 at the counter; €36.01 Premium Plus; +€1.27/page (Spain, Correos 2026)€0
AttachmentsPDFs, images and documents, certified together with the messagePrinted pages onlyYes, without proof
Can be automated from a processYes, as a workflow action with template and automatic filingNoYes
When it is still the right choiceAlmost any private B2B or B2C communication with a known emailWhen the law or the contract requires that form, or there is no email for the recipientRoutine operational communication with no risk

Price source: Correos (Spain), Burofax Premium and 2026 tariff for mainland Spain and the Balearics. Prices include VAT at the time of publication; check the current tariff.

The difference

Not a separate mailbox: a step in your process

Stand-alone certified email services give you the certificate. Dokuflex gives you the certificate in the case record, triggered at the right moment, with signature and AI in the same workflow.

Fires on its own

By condition or deadline

Invoice 30 days overdue, GDPR request 5 days from the deadline, contract with notice due in 60 days: the Dokuflex BPM workflow sends the certified email without anyone having to remember.

Evidence in its place

In the case record, not in a mailbox

The certificate sits alongside the contract, the invoice or the employee file with its permissions and retention period. When the lawyer asks for it, it is where it should be.

Same workflow

Notify and sign

If you also need the recipient's agreement, the same flow sends the document for eIDAS electronic signature and certifies the communication. One body of evidence, not two tools.

AI on the reply

Reads what they answer

Dokuflex AI classifies the reply (payment, dispute, silence) and moves the case to the next step, with human validation when confidence falls below the threshold.

Pricing

Pay per item sent. No lock-in, no minimums.

Certified email is included in the Dokuflex platform: you do not sign up for a separate service or pay a monthly fee to keep a mailbox. Each item costs a fraction of the cheapest registered letter, with no limit on pages or attachments within the email size, and the evidence is filed at no extra cost.

  • Free plan to try it with real emails
  • Volume bundles for law firms, accounting practices, insurers and utilities
  • REST API and integrations with your ERP or CRM to send from where you already work
Example: 40 payment demands a month
40 online burofax (€8.71)€348.40
40 burofax at the counter (€12.72)€508.80
Hours of admin, printing and travelNot included
40 Dokuflex certified emailsA fraction · 0 trips

Calculated with the Spanish Correos 2026 tariff for a single page. Ask for the exact rate for your volume in the demo.

Certified email for business: the alternative to registered post

Dokuflex certified email is an electronic registered delivery service under the eIDAS Regulation: every email goes out with proof of sending, delivery, full content and a date sealed by a trust service provider. It replaces registered post and the burofax in debt collection, employment communications, contract changes and notices to customers and suppliers, with the evidence ready in seconds and at a fraction of the cost.

Legally provable notices automated from your processes

Unlike a stand-alone certified email service, in Dokuflex the notice is an action of the process: it is generated from a template with the case data, sent when a deadline or condition is met, and its certificate is filed alongside the contract, the invoice or the employee file in the document management system. One platform to notify, sign, file and audit.

Certified email with eIDAS timestamping and verifiable evidence

The PDF evidence certificate includes sender, recipient, time-stamped events, the SHA-256 hash of the message and of each attachment, and is electronically signed so that any third party can verify it without depending on Dokuflex. Read more about when a certified email is enough and when you still need registered post.

FAQ

What we get asked most

What is a certified email?+

It is an email sent through a trusted third party that records and time-stamps every milestone of the sending (dispatch, delivery to the recipient's server, opening and attachment download where possible) and issues an evidence certificate containing the full content and its digital fingerprint (hash). The eIDAS Regulation calls this an electronic registered delivery service (Article 3(36) and Article 43).

Is a certified email as valid as registered post or a burofax?+

Both are admissible means of evidence. Article 43(1) of Regulation (EU) No 910/2014 states that data sent and received using an electronic registered delivery service shall not be denied legal effect or admissibility as evidence solely on the grounds that it is in electronic form. Registered post remains the option when a rule or a contract expressly requires that form, or when the recipient has no known email address.

What proof does the evidence certificate contain?+

Sender and recipient, the date and time of every event with a timestamp, the full content of the message and attachments with their SHA-256 hash, the technical delivery record and the electronic signature of the certificate itself so that anyone can check it has not been altered. It is delivered as a PDF and filed in the process case record.

Does the recipient need to register or install anything?+

No. The recipient receives an ordinary email in their inbox, with the message and the attachments. They do not have to register, download an app or accept anything for the sending to be certified.

How much does a certified email cost compared with registered post?+

Under the Spanish Correos 2026 tariff, the cheapest online burofax costs €8.71 for the first page, €12.72 at the counter and up to €36.01 with custody, acknowledgement and certified copy, plus €1.27 per additional page; comparable registered-post services in other countries cost similar amounts. In Dokuflex, certified email is billed per item sent, with no lock-in, at a fraction of that cost and with no limit on pages or attachments within the email size.

Can I send certified emails automatically from a process?+

Yes. Certified email is one more action in the Dokuflex process designer: a debt collection case, an employment communication or a response to a GDPR request can trigger it when a condition or a deadline is met, with a template, generated attachments and automatic filing of the evidence in the case record.

Is it suitable for employment communications such as dismissals or sanctions?+

Employment law in many member states requires written notice of dismissal and of serious disciplinary sanctions without prescribing a specific medium; in Spain that is Articles 55.1 and 58.2 of the Workers' Statute. A certified email proves sending, date and content, which is what gets disputed in court. It is worth combining it with an electronically signed acknowledgement when the company also needs signed receipt, and checking each case with your employment adviser.

How long is the evidence kept?+

The certificate stays in the Dokuflex document management system with the retention period you configure per document type (six years is the prudent reference in Spain under Article 30 of the Commercial Code; other countries have comparable rules) and you can export it at any time. Verifying the certificate does not depend on your remaining a customer.

Next step

Send today the demand you have been putting off for weeks

Create your account, write the email and receive the evidence certificate in seconds. Or book 20 minutes and we build the notification workflow for your case with you: debt collection, HR or GDPR.