As explained in the Mercurius section of the page "e-invoicing strategy of the Belgian public sector", the Mercurius platform acts as a central "electronic mail-room" for all Belgian public sector entities. the pages "Mercurius for the private sector"  and "Mercurius for the public sector" provide more specific information applicable to their respective target audience.

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1. Occasional suppliers of the Belgian public services, and more frequent suppliers who haven't yet switched to full electronic invoicing (machine-to-machine): they can use the site to create and send their invoices, and to follow up the processing of it. They can also follow up test invoice flows (see further)
2. Other suppliers: they can follow up the processing of the invoices they issued.
3. Customers: they can see the list of invoices that were sent to them by all their suppliers, and look at invoice details up to level of exchanged messages. This allows them to handle suppliers questions about invoicing much more efficiently.
4. IT operators (service providers, customer backend teams, access points,  ...) : they have the possibility to follow up the flows that relate to their services.  (NB: the present help section does not contain specific information for this target group. For more details, please contact the support through the online assistance request form.

What do I need to access and use the site?

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1. Belgian eID: we need to identify you with certainty, so the Belgian electronic identity card is required. Assistance to the installation and use of the eID is available on eid.belgium.be
2. only authorized individuals can send invoices and consult invoicing flows on behalf of companies (legal entities). All legal representatives recorded in the CBE have automatically access to the site on behalf of their respective legal entities. Other individuals, such as invoicing/accounting responsibles, need to first get the role 'billing officer' assigned to them. The following article discusses how to access the Mercurius Portal in a practical and comprehensive way: "How get access to Mercurius portal?".

What are the main sections of the site?

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If you have specific questions on the use of the site, don't hesitate to generate an issue on online assistance request.

Practical issues (business)

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Not all governmental entities are ready to receive invoices. If your customer does not appear in the customer selection list/search field, then it is probably not yet ready. Please contact your customer's procurement responsible (for the Flemish Regional authorities, you can also contact e.procurement@vlaanderen.be). Tip: to be certain about the official name of your customer ask its enterprise number and look for the corresponding official name on Crossroads Bank for Enterprises (CBE)

New invoice: supplier name does not appear, only enterprise number. How comes?

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I have an eID but I don't know how to use it.

Please visit eid.belgium.be. This site contains all the information required to install and use the eID. If you still have issues then please fill in our online assistance request form at support requested.

I have logged in but I receive an error message 'Sorry, you are not registered as company legal representative or billing officer'.

It means that the site has not found a link between you and a legal entity ( a company or public administration). Please refer to 'What do I need to access and use the site?'

Mercurius, legal functions and roles management (billing_officer)

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As stated in section "What do I need to access and use the site?"', only authorized individuals can send invoices and consult invoicing flows on behalf of companies (legal entities). The usual way to holding such an authorization is being a legal function holder, duly recorded in the CBE. The CBE Public Search site allows you to control the list of such functions: Crossroads Bank for Enterprises (CBE).

The other option is to use the eGOV roles management system. This system is available for all legal entities. It gives them the possibility to assign and revoke roles to their employees (or subcontractors), to perform administrative duties online on their behalf, in eGOV applications (such as the Mercurius web site). However, to be able to use it, a chief access manager must be designated by a legal function holder. Optionally, the chief access manager can appoint a (local) access manager for the domain "Finance". If there is no chief access manager for your company, or if you don't know him, then you must first contact CSAM to know the person in charge of this responsibility, or initiate the assignment of a chief access manager. These managers will be able to designate billing officers for their enterprise, using the tool My eGov role management).

In practice

The following article discusses how to access the Mercurius Portal in a practical and comprehensive way: "How get access to Mercurius portal?"

Mercurius/Production, Mercurius/Test: what is it about?

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If you still have questions after going through this FAQ list, then please fill in our online assistance request form. Our support staff will handle your request. Please be aware that providing correct, detailed and specific information makes user support much more efficient.