As from 1st January 2013, electronic invoices and paper invoices are treated equally in Belgium.

janv. 1, 2013

Since 1st January 2013, electronic invoices and paper invoices have been equivalent. This means that you can electronically create, send, receive and archive your invoices.  The electronic invoicing is not only of interest for large companies, but as well for self-employed workers and small and medium enterprises.

http://www.efacture.belgium.be/