The viesClient.exe client application allows for quick and automatic checking of entities (contractors) from the command line level (CLI / CMD) in terms of their current status in the VIES system. The application also allows you to save the downloaded data to a file in 3 formats:

  • JSON (default display format to stdout)
  • XML
  • MAP (attribute map key = value)

Application has been successfully tested in the following versions of MS Windows: XP, 7, and 10.

The latest version of the application is always available for download from the Download page.

The full functionality of the application can be checked – without the need to create an account – using the provided Test API

To use the add-in in the production API, you need to set up an account on the website, purchase a minimum of the Business plan and generate an API key and API key identifier.

The process of registering and setting up an account as well as generating keys has been described on the Documentation website.


The shared executable program viesClient.exe does not require installation and does not have to be run under an account with administrative privileges. To run the program, select the Command Prompt application from the Start menu or type cmd in the “Search programs and files field and press Enter:

After starting the console, go to the directory where the zip file with viesClient.exe was downloaded and unpacked.

Starting the program without specifying parameters displays the help window.


Launching the viesClient.exe application without specifying the API key ID and API key allows you to query the test environment (more details on the Test VIES API page).

In order to connect to the production environment, it is necessary to call out the viesClient.exe application with the authentication parameters, which are:

  • keyid – the parameter should contain the API key identifier (ID) generated on the account on the website,
  • key – the parameter should contain the API key (Key) generated on the account on the website.

Details on generating the identifier and key are described on the Documentation page. Below is an example of calling the application with authentication parameters (keyid and key):
viesClient.exe -keyid XXXXXXXXXXXX -key YYYYYYYYYYYY -vies -euvat PL7171642051.

Calling syntax

Syntax of calling the viesClient.exe program:
viesClient.exe <action> [options].

Available actions <action>:
-help – description of program calling parameters
-account – returns information about the current account balance of
-vies – get company data from VIES.

Available options [options]:

-keyid string – API key identifier
-key string – API key
-euvat number – EU VAT ID number with country prefix
-format type
– format of the returned data (JSON, MAP, XML), default: JSON
-file path
– name and path to the result file, default: viesClient.exe run directory
-proxy url
– HTTP proxy configuration (as URL http://user:password@hostname:port).


ATTENTION! The following examples are adapted to the data collected in the test environment. To perform checks on the production environment, add the –keyid and –key parameters with the appropriate values to each query.

1. Downloading company data from VIES and displaying the result on the console in MAP format:

viesClient.exe -vies -euvat PL5213003700 -map format

2. Display information about the current account status:

viesClient.exe -account.

3. HTTP Proxy setting:

viesClient.exe -vies -euvat PL7272445205 -proxy http://user:password@