Switzerland announced on Friday it would reduce the number of Lockheed Martin F-35A Lightning II fighter jets it is buying from the United States to stay within the original budget after costs increased significantly.

Background on the Deal

Bern selected the F-35A as its next-generation fighter plane in 2021 for what it considered a fixed price of 6 billion Swiss francs ($7.54 billion) for 36 jets. The purchase was approved by Swiss voters in a narrow 50.1% referendum in September 2020, and the government formally signed the contract in September 2022 for CHF 6.035 billion.

However, the United States later said that sum was a misunderstanding and that the price was not fixed.

Cost Overruns Force Reduction

Following a cabinet meeting on Friday, the Swiss government instructed the defence ministry to procure the highest possible number of F-35As within the 6 billion franc budget that was narrowly approved by the public in the 2020 referendum.

“Due to foreseeable cost overruns, maintaining the originally planned number of 36 F-35As is not financially feasible,” the government said in a statement.

In June 2025, Switzerland reported that the U.S. Joint Program Office wanted to raise the price by up to $1.3 billion. By August, cost overruns were estimated to be between $806.8 million and $1.6 billion, driven by inflation, rising commodity prices, and trade tensions.

Tariff Complications

The purchase was further complicated by trade tensions. The Swiss government this summer restated its commitment to buying the jets even after the United States imposed 39% tariffs on Swiss goods exports in August 2025, the highest rate on any Western country.

Politicians called to cancel the deal after Trump’s tariff announcement, questioning whether Switzerland should proceed with the purchase from a country imposing such steep tariffs.

Following negotiations in November, the tariffs were reduced to 15%, bringing Switzerland in line with the European Union. As part of the deal, Switzerland committed to $200 billion in U.S. investment through 2028.

Potential to Reach Original Target

The government said that pending examination of whether further steps are needed to boost Switzerland’s defence capabilities, the cabinet could make a decision that would potentially enable it to reach the original target of 36 jets.

Long-Term Defence Planning

Given changes in the security situation, the defence ministry will take steps to modernize Switzerland’s air defences under planning that envisaged the country requiring 55 to 70 modern fighter jets.

That potential increase in the number of aircraft on top of the F-35A purchase would be reviewed independently of the aircraft type, the government said.

The new jets are intended to replace Switzerland’s aging fleet of F/A-18 Hornets, which are scheduled to go out of service around 2030. Deliveries of the F-35As are planned between 2027 and 2030.