The year is almost over: is your organisation ready to migrate Suomi.fi Messages to REST?

Official authority messages sent to Suomi.fi Messages will, from 1 January 2027 onwards, be transmitted through a REST interface. If your organisation uses Suomi.fi Messages, now is the time to make sure that you have planned and scheduled all actions necessary for the migration. By taking action now, you can ensure that your clients will continue to receive important messages through Suomi.fi Messages.

What does the change mean for the organisation?

If your organisation is not using the REST interface and is not planning to introduce it either, you will no longer be able to use Suomi.fi Messages from the beginning of 2027.

Therefore, make sure that your organisation has plans and schedules in place for the REST migration in advance. Otherwise, your organisation must find another solution for arranging official electronic communications. Please keep in mind that authorities and organisations with public administrative duties have a statutory obligation to use Suomi.fi Messages for notifications. If the service is not in use, your organisation must apply for an exemption.

It is best to take care of everything necessary for the migration in good time as interface introduction, testing, and possible fixes will take time. You can find support for planning the migration through the Suomi.fi for Service Developers REST migration guidelines.

Although the migration is an obligatory technical change, it also offers a good opportunity to take a look at your organisation’s overall electronic communications and to expand the use of Suomi.fi Messages to new services.

Five things you should do if you have not done them yet:

1. Prepare a REST migration plan and schedule.
2. Review the division of responsibilities related to the migration together with your system supplier.
3. Reserve time for the introduction, testing, and transition to production.
4. Assess the possibilities of expanding the use of Suomi.fi Messages. The migration to the REST interface offers a good opportunity to examine if your organisation could be using Suomi.fi Messages more extensively in the organisation’s services and processes.
5. Don’t forget to notify about the changes. If you implement any changes to the extent of the service use or the operating methods, you should notify personnel, customer service, service owners and, if necessary, customers.

A good place to start planning is the Administrative deployment guidelines on Suomi.fi.

Decide at least on the following aspects:

• Who is responsible for the transition?
• When will the REST migration take place?
• Could Suomi.fi Messages be introduced in more services at the same time?

What does the REST transition require?

The earlier you begin preparing for the migration to REST, the more control you have over the migration.

It is recommended that you go through the whole implementation with the system supplier well in advance in order to guarantee a smooth migration. The system supplier handles system changes related to the migration from the WS and SFTP interfaces to the REST interface.

The SMTP interface, i.e. the email interface, cannot be migrated into or converted to a REST interface. Read more about changes related to the SMTP interface on the Suomi.fi for Service Developers website.

The REST transition also requires action from the organisation itself. The organisation must:

• submit the data related to the interface introduction through the service form to the Digital and Population Data Services Agency (which system and which services will migrate to the REST interface);
• participate in testing; and
• ensure that the service works as planned in its processes before transitioning to production.

In addition to ensuring that the technical connection works, you should also check that the messages, attachments, service names and other key functionalities are working as they should.

If you need support, contact the deployment team for Suomi.fi Messages at the Digital and Population Data Services Agency (viestit-kayttoonotot@dvv.fi).

The migration to the REST interface in Suomi.fi Messages has been consistently notified to users since 2024. New connections to the old APIs have not been made since early 2025, and no new services have been added to the old connections since the beginning of 2026.

Niina Viitanen, Senior Specialist, Digital and Population Data Services Agency