The way Belgian providers handle utility subscriptions is confusing: the consumption point is referenced by a EAN (European Article Number), each counter has a different number, and both normally don’t appear on invoices. Invoices (including electronic ones) in turn have totally unrelated and cryptic references. Lucky if you have only one counter for each commodity. Normally, you can manage all online, plus the option for automatic payment (from Belgian bank accounts).
The Belgian consumers’ association offers a tariffs comparison table here: https://www.test-achats.be/maison-energie/gaz-electricite-mazout-pellets/calculateur/energie-qui-deviendra-votre-fournisseur/?landingpage
Gas & electricity
The electric grid is managed by former state monopolist www.engie.be (who also operate as provider).
Water (Eaux)
The local water system is provided by https://www.vivaqua.be/en/. Administrative response notoriously slow.