Before starting to lodge declarations via message exchange, the company must test the functionality of its software with Customs and that the messages the software produces conform to Customs’ specifications. At the same time, the data communication links are also tested. When the company’s application has been processed, Customs will contact the company to arrange a consultation and to set the dates for the testing. The company is to build its own declaration system independently based on Customs’ message implementing guidelines.

During the testing, the company submits declaration messages with varying data content (for example complete or amended declarations or additional information), to which Customs then responds with messages (acceptance, error, request for additional information, etc.). The company must respond to the reply messages as required, for example by correcting errors or sending additional information.

The company is to reserve an uninterrupted work period of three to five weeks for the customer testing. The duration of the testing depends on the system to be tested, the number of messages to be submitted and the content of the declarations. After successfully completing the testing phases, the company will receive the decision on message exchange authorisation and can enter the production phase of message exchange on the date specified in the decision. If the time reserved for testing is exceeded, the testing will be interrupted and the company must schedule a new time for the testing. This may mean postponing the final testing considerably.

Testing service for direct message exchange

The message exchange testing service enables our customers to test declarations for direct message exchange independently.  You can now use Suomi.fi identification to log in to the service. The Suomi.fi mandate code used in this service is “Message exchange with Customs”. The customers are able to test their own systems against the Customs interface and to verify that their systems can correctly produce the declarations messages to be sent to Customs and handle the reply messages from Customs. Independent testing requires the authorisation for direct message exchange issued by Customs and the registration of the company’s information in the testing service.

In the testing service, customers can test

  • Transit declarations and test cases for authorised consignees
  • test cases for import declarations (UTU)
  • test cases for standard customs warehousing declarations (UTU)
  • export declarations in direct message exchange
  • sending attachments to import and export declarations by message to Customs via direct message exchange. This functionality is tested only by software suppliers.

Manual for the message exchange testing service (pdf)

Customs message exchange testing service (video)

Identification in Customs’ e-services


System-specific testing of Customs’ systems

UTU Import and Customs warehousing
1) Testing partly in the message exchange testing service
2) Technical testing

AREX Summary declaration system
1) Technical testing
2) Parallel testing

ITU import system
1) Technical testing
2) Parallel testing
3) Testing with own declaration material (changing over from message exchange via an operator to direct message exchange)
4) Testing the attachment message service with the message exchange testing service (software suppliers)

NCTS transit system
1) Technical testing
2) Deployment testing
3) Testing with own declaration material (changing over from message exchange via an operator to direct message exchange)

ELEX export system
1) Testing with the message exchange testing service 
2) Testing the attachment message service with the message exchange testing service (software suppliers)
3) Testing the amendment and invalidation messages with the company’s own declaration material

ELEX export system, “Arrival at exit” message
1) Technical testing

Intrastat, statistics system for intra-EU trade
1) Testing with the customer’s own material.

Technical testing of the connection

Before the actual system testing, the company applying to start using direct message exchange must test the connection via a public message interface from the company’s system to the direct message interface of Customs. If the company or the service provider used by the company has carried out the technical testing earlier, no new testing is needed.

The technical testing of the communications for direct message exchange consists of three test cases (four if the customer starts using the Message Notification Service). The communications are working if the web service of the direct message exchange reports the receipt of the message. In addition, the customer has to be able to retrieve the reply message from the Customs message storage. The content of the reply message (acceptance, rejection etc.) is not significant for the testing of the communications.

Testing with the Message exchange testing service

The company carries out the testing independently in the testing service using the system-specific test cases determined by Customs. In the testing service, the customer testing official determines the time to be used by the company for testing as well as the test cases which the company must complete to pass the testing. The testing service carries out all the measures the testing requires and guides the customer during the testing.

Technical testing

The technical testing is carried out with the Customs testing official using the test cases created by Customs. The aim of the technical testing is to ensure the functioning of the message exchange between Customs and the company and to test the correctness of the message structure.

Parallel testing

In parallel testing, the company’s own declaration material is used as test material. Customs compares it with the data in the messages sent by the customer. The aim of the parallel testing is to ensure that the company has sufficient competence for providing correct declaration data. Therefore, all the persons who will be completing declarations for the company should participate in the parallel testing.

Testing with own declaration material

The company uses its own declaration material for the testing. The company chooses the material, and it shall contain the data specified by Customs.

System-specific instructions for customer testing


AREX message exchange customers (pdf, 421 kB)

Guide for applying for summary declaration customer status

Testing instructions for export system ELEX

Customer testing for direct message exchange in export is carried out with the test automation application. In the testing service, there are the test cases for export declarations and attachments, created by Customs.

Testing instructions for the transit system

Testing instructions for customs warehousing (UTU system)

Message exhange customer status in customs warehousing (pdf, 403 kB)

Guide to customs warehousing for message exchange customers

Testing instructions for temporary storage (UTU system)

Testing instructions for the statistics system Intrastat

Testing instructions for the import system ITU

Testing instructions for import (UTU system)

Customer guidebook on message exchange for transit-related declarations (Customs Clearance System UTU)


Any questions?

Instructions regarding special matters (authorisations, guarantees and initiating message declaration)
Mon–Fri 8 am–4.15 pm

For example, you can ask about following subjects:

  • when to apply for an authorisation that is granted by Customs and which are the authorisation requirements
  • when is a guarantee required of me
  • when to initiate message declaration and what does it require of my company.

We aim to answer your enquiry no later than within three working days. If the matter is urgent, you can call the “General instructions for businesses” service number.