Procedure to access the Filing application

To access the CBSO Filing application, a modern external interface is used, CSAM, the portal for online government services.

Various types of digital keys can be used to log in.

Logging in with an electronic ID card via CSAM

You can use your identity card and an eID card reader to log in. This is the standard procedure to access various Belgian government online services and guarantees the highest level of protection.

To log in with your eID, you will need the following:


Your eID card. Always insert your eID in the card reader before going to the online portal.


A four-digit PIN.


Appropriate software to use your eID. This can be downloaded for free at Download eID software (

eid reader A card reader::
  • Built-in card reader: Some computers and keyboards have a built-in card reader.
  • Stand-alone card reader: You can easily connect a stand-alone card reader to your PC with a cable.

If you have questions about how to use your eID, please visit the CSAM Help Centre (eID card reader).

Logging in with an eID card reader - YouTube

Logging in with itsme, your digital ID via CSAM

You can use your digital ID to log in securely with your smartphone.

In order to use this option, you must first register with itsme.

You can find more information about itsme and how to register in this brochure and at itsme®-app | Ontdek itsme®

If you have questions about itsme, please visit the CSAM Help Centre (itsme®).

Logging in with an EU-recognised login tool with eIDAS via CSAM

Citizens of other European Union countries can use eIDAS to log into Belgian government online services with their national means of identification and authentication.

A list of countries for which a national identifier can be used to log in can be consulted by choosing “Log in with an EU-recognised login method” when logging in to an online service. 

More information can be found on this web page.

For questions about eIDAS, please visit the CSAM Help Centre (eIDAS).

For help logging in to the government's online services, please visit the CSAM Help Centre.

If you cannot find the answer to your question in the Help Centre, you can contact the online public service you wish to access. For details, go to Contact us | Help Center (

More information on CSAM can be found at

Logging in by other means via IDAAS

For foreign nationals and third-party declarants who cannot use an eID, itsme or eIDAS to log in, access by means of an electronic certificate by name has been provided through IDAAS (Identity As A service) since 23/01/2024.

Accounting firms can also log in through this new access using a commercial certificate.


Log in via IDAAS with an electronic certificate.

Only the following electronic certificates may be used:

A list of supported Certificate Authorities (CA) can be found here.

When prompted, select the certificate you wish to use.

Enter your PIN code.

Logging in via CSAM with your commercial certificate will no longer be possible from 01/02/2024.

More information on the IDAAS solution can be found on our website