REST API

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SecuMailer has a REST API for sending secure emails. Both the GDPR and the NTA 7516 functionality are fully accessible via this API.

The API is documented with OpenAPI specification 3.0.1.

The REST API has webhook functionality, which means that the SecuMailer platform can communicate email events with an HTTPS endpoint of the sender.

SMTP API

The SMTP API is usually the simplest integration option for many backend applications because backend applications often have a provision for an SMTP client on board.

We have successfully integrated for customers with Salesforce, SAP and Centric. We have also successfully integrated with patient file systems such as Medisoft Dossier Manager.

GraphQL API

The SecuMailer platform offers insight into email events. This can be done on the basis of a (push) webhook call (see REST API above) and on the basis of a (pull) GraphQL endpoint.

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eIDAS Qualified Registered Email

The smarter alternative to a registered letter: faster, safer, and more cost-effective

Why wait for a registered letter to be delivered when you can send a legally binding, fully compliant message in seconds? With SecuMailer’s eIDAS Qualified Registered Email, you get the same legal status as a registered letter but without paper, postage, or delays.

Instant, secure, EU-wide compliance, and effortless for both sender and recipient.

SecuMailer is the only Dutch qREMS provider on the EU Trusted List.
Delivering the highest level of trust for legally binding registered email, recognised across all EU member states.

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e-IDAS

Legal Certainty

Same legal status as a registered letter, recognised EU-wide.

Save time

Type, send, and deliver instantly, no postal delays.

Cut Costs

Reduce costs by up to 10x compared to physical registered post.

Stay compliant

100% GDPR, NTA 7516, and eIDAS proof. All data stays within the EU.

Why Choose Qualified Registered Email?

When a message needs to hold up in court, standard secure email isn’t enough. eIDAS Qualified Registered Email gives you the legal certainty, speed, and cost savings your organisation needs without compromising privacy or ease of use.

Perfect for legal notices, government decisions, financial statements, contracts, compliance notifications, and any communication where proof of delivery is critical.

How eIDAS registered mail with SecuMailer works

From send to secure in five seamless steps.
Step 1

Write and send

Write your message in your usual email client, such as Outlook, Microsoft 365, or Google Workspace. Simply send it with one click.

Step 2

Qualified timestamp and proof generation

As part of the delivery process, the message is sealed with a qualified electronic timestamp and every step, from sending to delivery to receipt, is logged in a tamper-proof audit trail. This process makes your email legally valid.

Step 3

Recipient authentication

The recipient receives a notification and authenticates their identity. After that, the registered email is delivered directly to their inbox. This ensures the message reaches the right person, securely and verifiably

Step 4

Direct inbox delivery

Once authentication is complete, the email is delivered directly to the recipient’s inbox. Once it’s delivered, the email is removed from our server.

Step 5

Proof of delivery

Both sender and recipient receive confirmation of delivery including proof that holds up in court.

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Product Features of registered email

  • Email from your own email environment
  • Delivery to the recipient’s mailbox
  • Every email always secure
  • Delivery without portal intermediaries
  • No additional installation or extra software required
  • Works with all email clients
  • Works on all devices
  • Integration with back-office systems possible
  • Delivery receipt available
  • Functional / shared mailboxes possible
  • Custom branding applicable
  • Standard attachment size up to 40MB
  • Send up to 5TB with SecuFiler
  • Integration with any professional mail server
  • Implementation based on existing features
  • Security based on existing features
  • Security based on transport rules
  • API integrations available
  • (Audit) logging available
  • Two-factor authentication based on SMS
  • SAML / SSO available for the management environment
  • GDPR
  • Data minimization
  • ECSO (European Cyber Security Organization)
  • ISO 27001
  • NEN 7510
  • NTA 7516
  • eIDAS
  • ISAE 3000 SOC 2 Type 2
  • Personal service
  • Easily reachable by phone
  • Service commitment: uptime 99.95%
  • Service and support from 9-17
  • Self-service portal
  • Monthly SLA reports

Proven across sectors where every delivery counts

Municipalities

Government & Municipalities

Communicate confidentially with citizens, departments, and partners, fully compliant with GDPR. Align with eIDAS requirements for legally registered digital delivery, with full traceability. SecuMailer delivers secure messages directly to the recipient’s inbox: a simple and secure way to share sensitive decisions, notifications, and documents. It’s secure, accessible communication without barriers.

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Health-Care

Healthcare providers

Send patient records, referrals, and lab results securely and in full compliance with NTA 7516 and GDPR. SecuMailer integrates with your EHR system and enables secure email that meets healthcare standards ensuring interoperability across organizations. Need to reach a patient? Your message arrives directly in their inbox: no portals, no repeated logins, just secure and accessible communication.

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Finance

Legal professionals

Communicate confidentially with clients, courts, and legal partners fully compliant with GDPR. Need legal proof of delivery? SecuMailer supports eIDAS-compliant registered email, ensuring full traceability and legal validity. For regular confidential messages: secure emails arrive directly in the inbox, with no portals or logins required. A flexible solution for both formal and everyday legal correspondence.

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Legal

Financial institutions

Send sensitive documents like payslips, tax returns, or financial statements securely and GDPR-compliant. With SecuMailer, you reach clients directly in their inbox, without requiring a portal or login. Need legal proof of delivery? Our eIDAS-compliant registered mail gives you full traceability. It’s professional, secure communication made simple for both you and your clients.

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business

Business Services

Whether you're sending contracts, proposals, reports, or personal data, SecuMailer ensures your emails are secure and fully GDPR-compliant. Messages are encrypted and delivered straight to the recipient’s inbox, without requiring portals, accounts, or logins. It’s a professional, accessible way to protect sensitive communication and strengthen trust with your clients.

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Housing

Housing & Property Management

Send rent contracts, payment reminders, or tenant communications securely and in full compliance with GDPR. SecuMailer lets you reach tenants and partners directly in their inbox. Need legal proof of delivery? Use our eIDAS-compliant registered email with full traceability.

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It’s just like registered mail – but it works like email.

Ditch the paper. Send instantly. Stay legally covered.
With eIDAS Qualified Registered Email, you ensure that your critical communications are delivered instantly, securely, and with full legal validity.

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See how easy secure emailing can be
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