Belgium has opted for the F-35A as its future combat aircraft, becoming the 13th nation to join the program.
The country joins other European nations, including Italy, the UK, the Netherlands, and Turkey, that have opted for the Lockheed Martin fighter.
"We have landed! With the purchase of the F-35... we assure your safety and that of our military," Belgian Defence Minister Steven Vandeput said.
"The purchase procedure for a new fighter aircraft should be an example for all other federal purchases."
Belgium has secured a low price for the F-35, with the deal coming in several billion euros lower than the government's budget over the 40-year life of the program.
Reports indicate that the price per plane will be around 76 million euro (roughly AU$121 million).
In a statement, Lockheed Martin said it "looks forward to extending the relationship with the Belgian government and industry participants for decades to come."
Airbus, which offered the Eurofighter, issued a statement expressing disappointment at the decision.
"Airbus Defence and Space accepts this decision by Belgium and is aware of the strong links between Belgium and the US on defence industrial matters. Therefore, yesterday’s decision does not come as a complete surprise.
"However, Airbus Defence and Space remains firmly convinced that the offer submitted by Team Eurofighter...would have represented a superior choice.
"It is a lost opportunity to strengthen European industrial cooperation in times when the EU is called upon to increase its joint defence efforts."
Australia recently took delivery of its 10th F-35 at Luke Air Force Base, Arizona.
The ninth and tenth aircraft will operate on the Australian Autonomic Logistics Information System (ALIS) which performs maintenance management, fault diagnostics, supply support, mission planning and training management across the F-35A fleet.
Two of Australia’s F-35A aircraft are scheduled to arrive for permanent basing at RAAF Base Williamtown near Newcastle in NSW in December.