Registered E‑mail API allows you to integrate sending registered e‑mails within your existing e‑mail flows. Registered e‑mails can be sent automatically and the status of each e‑mail can be monitored in real-time.

The recipients do not have to register themselves, log in or install specific software. They can retrieve or refuse the message and the attached documents from their own e‑mail environment, from any device at any time.

This API offers the following functionalities:

  • Create new users.
  • Send registered e-mails.

API specification

Test the API on SwaggerHub

Base URL

Conceptual model

Conceptual model



iDIN is a service offered by banks, which allows consumers to identify themselves with their bank's secure and reliable login methods.


A hash code is calculated for all submitted attachments to secure the authenticity of the message.

Registered E‑mail announcement

After sending the registered e‑mail, an announcement is sent to the recipient. The recipient can accept or reject the registered e‑mail. After acceptance, the recipient will receive the registered e‑mail in their own e‑mail environment.

Registered E-mail status summary

The service tracks where your registered e‑mail is in the sending and receiving process. You can check the status of the registered e‑mail in 3 different ways:

  • Check the delivery e‑mail in your inbox.
  • Check the online dashboard.
  • Check through an XML interface (optional).

API workflow

API workflow


If you have security protocols set up, please contact Registered E‑mail for additional configuration of the environment.

For example:

  • DomainKeys Identified Mail (DKIM).
  • Domain-based Message Authentication Reporting & Conformance (DMARC).


  • Sends registered e‑mails via the API.
  • Speeds up the document signing process with the digital signature functionality.

Setting up your third-party accounts

To start e‑mailing with the Registered E‑mail API, you need to create a Registered E‑mail user account.

Use the API request POST /api/user/ to create a new user on the Registered E‑mail platform.

You need to create an user for every person in your organization that needs to send registered e‑mails You only need to provide an e‑mail address.

How to...

Create a user

This endpoint creates a new user (with the role of user):

POST /api/user/ See on Swaggerhub

Send the e‑mail address of the new user in the request body:

^^Request body^^
  "email_address": "",

A successful response returns the user ID:

  "id": 154

The new user receives an e-mail from, asking to activate the Dashboard account.

Send registered e‑mails

Use this endpoint to send registered e‑mails:

POST /webservice/mailsender/send See on Swaggerhub

Send the following details in the request body:

^^Request body^^
  "message_body": "this is the e‑mail body",
  "sender_email": "",
  "sender_real_name": "Jane Doe",
  "subject": "this is the subject",
  "x-own-id": "id",
  "x-own-guid": "guid",
  "x-own-campaign": "campaign code",
  "recipient_email": "",
  "recipient_language": "en",
  "attachments": [
      "attachment": "BAse64E=",
      "attachment_name": "attachment.pdf",
      "attachment_type": "application/pdf"

Parameter Type Description
message_body string Content of the message.
sender_email string E‑mail address of the sender.
sender_real_name string Name of the sender.
subject string Subject line of the e‑mail.
x-own-id string User ID.
x-own-guid string Globally Unique Identifier (GUID).
x-own-campaign string Campaign code. Allows to filter sent-emails using this code, for example 1234. Optional.
recipient_email string E‑mail address of the recipient.
recipient_language string Language of the recipient.
attachment_name string Name of the e‑mail attachment.
attachment_type string Document type of the e‑mail attachment. Supports are all common document types.

A successful response returns the ticket token and the ticket URL.

  "ticket_token": "K.SF1m-w",
  "ticket_url": "",
  "message": "OK"

Parameter Type Description
ticket_token string This is the ticket token.
ticket_url string Ticket URL.
message string Success message.

Return codes

Code Description
200 Success.
201 Created.
202 Accepted.
302 Found. Link in location header.
400 Bad request.
401 Unauthorized.
403 Forbidden.
404 Not found.
405 Method not allowed.
412 Precondition failed.
429 Too many requests.
500 Internal server error.
502 Bad gateway.
503 Service unavailable.

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