On the Brussels–Liège axis: to Brussels, Liège and Germany
The E40 runs right through the region, and it largely decides which airport you choose. Heading west, you are quickly at Brussels Airport from Leuven, Herent or Kortenberg. From Aarschot and Diest, your driver joins the E40 via the E314; from Tienen and Landen, it is the E40 all the way. Do bear in mind the morning rush towards Brussels, which starts early.
Heading east, the same E40 takes you past Liège to Aachen, making Cologne Bonn and Düsseldorf easy options if you fly with a German airline. Live in Tienen, Landen or Zoutleeuw? Liège Airport is often an underrated choice for holiday flights. Charleroi is reached via the Brussels Ring heading south. And from Diest and the north of the Hageland, Eindhoven is an option too. The price table shows the fixed fare from your town to each airport.