Orange waste bags becoming compulsory in Brussels
As of 1st May 2023, orange waste bags in Brussels will become mandatory for all. it will only be collected once a week, however, how exactly the new rules will work has not yet been decided and it will be announced later.

White or orange bag, what's the difference?
The white bags are currently used to collect household waste that cannot be recycled. Once in your white bag, this “residual waste” is treated at the energy recovery center (incinerator). They are then used as fuel to produce electricity equivalent to the annual needs of 65,000 households and heat which makes it possible to heat, among other things, the nearby Royal Estate.
Since your food waste is 80% water, it does not really contribute to this production of electricity and heat. It is better to throw them in the orange bags in order to recover them as green energy and compost. Indeed, Bruxelles Propreté collects the orange bags which are recovered in biomethanation centers in Ypres or Herstal.
What waste to throw in your orange bag?
The orange bag is intended to dispose of your food waste only. For your garden waste, use the green bags provided for this purpose. Waste refused in the orange bag (bones, carcasses, crustacean shells, nappies, etc.) must be placed in the white bag.