Minor airports:

  • Eindhoven Airport (EIN), in 120 km – Served by Ryanair, Transavia and Wizz Air
  • Weeze/Niederrhein Airport (NRN), in 130 km – Served by Ryanair (No public transport to Aachen)
  • Brussels South Airport in Charleroi (CRL), in 150 km – Served by Ryanair and Wizz Air

These airports are less well connected by trains, so you may need to book a rental car to get to Aachen if you find suitable (low-cost) flights.