The cheapest way is to travel the distance between Amsterdam and Brussels by bus, for example, to the company Eurolines. Flights depart from Amsterdam's Amsterdam Amstel bus terminal, 3-4 hours later (if traffic jams) arrive at the Belgian CCN Noordstation station in the railway station of the Northern Railway Station. The ticket for one adult passenger costs from 10 EUR.

The next option is a train. It can be a high-speed train Thalys, which goes to Brussels about 2 hours. On the day from Amsterdam Centraal Station to Brussel-Zuid (it's Bruxelles-Midi or South), 11 flights depart, the ticket costs about 60-110 EUR depending on the class of the place, on the time and conditions of booking the ticket. You can arrive by an ordinary train, which arrives at the Central (Central) Station of Brussels in 2 hours 55 minutes. Travel on it costs cheaper, 40-64 EUR for 2 or 1 class respectively.

But the plane is better not to offer. A direct 45 minute flight can cost the tourist 300 and more EUR. So getting by bus and train will be more convenient and easier.