A Belgian tax return can be filed by an accountant or tax specialist on behalf of a taxpayer. This can only be done if a valid proxy has been validated by the tax payer.
Beware: proxies are always personal. Consequently, for married persons or legal co-habitants, both partners always have to provide their personal proxy (even if one of the partners has no income).
It is possible to set up an electronic proxy. The initiative to set up a proxy can be taken either by the taxpayer or by the consultant. The second method, where the consultant prepares the proxy is the easiest one.
Proxies are set up on the site ‘Mandates-CSAM’. If you click this link, you will first need to activate the access to the site (see further login process): https://eservices.minfin.fgov.be/mandates-csam/finances/
The site is available in 4 languages: Dutch / French / German / English
There are various methods to gain access to the site.
The easiest and most often used ones are:login with a Belgian e-ID card; you can only do this if you have a card reader for this type of cards and also if you have the 4-digit PIN (Personal Identification Number) that came with the card when you registered with the commune.
If you forgot the PIN code, a new one can be obtained, but to do so you have to visit the local communal authorities.
Login with the smartphone app: it is possible to create a login on your smartphone by downloading the app and following the instructions. Setting up Itsme can not only be done with the e-ID card, but also with certain bank cards and a card reader from the bank
The proxy can also be activated with other login systems, but these are not so often used:
It is the easiest if the consultant prepares the proxy so that you only have to access the system to validate the mandate.
The consultant needs the following:
If the consultants sets up the proxy, he can activate an e-message, inviting you to access the system and validate the proxy.
Also the taxpayer can initiate proxies. To do so, the system is to be accessed and the consultant can be selected. For ICHIBAN Consult, one has to select the reference number 0816638347 in the system and then further follow the instructions.
There are several proxies available in the system. In the site, one selects the language (top left side) and in the navigation bar, one selects the option ‘Create’ (pencil).
The system offers the possibility to enter a start date (default on the current date) and an end date of the mandate (not obligatory and advisable not to define this). You can also add a reference for the mandate (not obligatory) and the language, in which the system will further communicate.
ICHIBAN recommends to always set up multiple proxies:
In most cases, you can disregard the other proxy types.
It can happen that it is not possible to set up an electronic proxy through the website. There is a backup system, where you can complete a document to initiate a proxy:
You then need to go to the following page:
Please note that you have to personally sign the document and have to send the completed and signed document by regular mail to the consultant, together with the requested documents. Please note that the original copy must be sent (a scan of a signed document will not be accepted by the authorities).
Upon receipt of the documents, the consultant can contact the tax authorities to activate the proxy. This proxy type only covers the filing of a non-resident tax return, and can not be used for any other purpose.