The car park under Belval Plaza is run by Indigo and is open 24 hours a day, every day. It is the closest parking to the Plaza’s shops, the Kinepolis cinema and the restaurants along avenue du Rock’n’Roll.
It is paid parking. Check the current rates at the entrance or on Indigo’s page before you settle in for a long stay; if you are driving in to take the train, the P+R by the station is the better choice, because it becomes free when you carry on by public transport.
More on parking and every way into Belval: Getting to Belval.