Charter airlines TUIfly Belgium have introduced two new Caribbean destinations for summer 2018 schedule. Since June 2018, travelers in Brussels will have great opportunity to fly either to Aruba or Curacao (together with Bonaire so called ABC Islands). Flights are operated with Boeing 787-8 Dreamliner and with one stop in Santo Domingo, Dominican Republic. (no aircraft change). At this moment you can book first minute deals to both islands from €400. Note that there is no checked bag included in base fare and you need to purchase extra. (it is €40 for 20kg bag both ways).
UPDATE.: This deal has expired. You can follow here to latest offers from Brussels to Aruba or Curacao here.