WASHINGTON — The estimated cost of buying the F-35 Joint Strike Fighter has risen in recent years, but the Defense Department now expects to spend less money overall on the stealth jet compared to earlier projections, according to a recent Pentagon report.
In all, the Pentagon anticipates it will cost about $536.3 billion to acquire all planned copies of the tri-variant F-35, according to what’s known as a modernized selected acquisition report (MSAR) released by the Pentagon [PDF] that covers the year 2025. That’s up from $485.2 billion in a previous MSAR published in 2024. The estimates encompass development and procurement costs.
But when calculating the price of operating the jet over its lifespan, the Pentagon expects to spend a total of roughly $1.93 trillion. While an eye-popping sum, the projection is slightly lower than a total expected cost of $2.06 trillion listed in the MSAR published in 2024. (The valuations account for inflation to estimate costs in the year of purchase.)
The overall lifecycle estimate is essentially an educated guess for what prices might look like over the next six decades. The figure accounts for most conceivable costs associated with operating the jet, like the price of fuel and staffing, as well as more complex technical estimates, such as sustainment and future upgrades. Costs fluctuate for a number of factors, such as “affordability initiatives” that the document says have helped lower anticipated spending and changes to the cost of materials and projected manpower.
The F-35 — which comes in a conventional takeoff and landing “A” model, a short takeoff and vertical landing “B” version, and a carrier-capable “C” variant — is operated by the Air Force, Marine Corps and Navy. The jet is built by defense giant Lockheed Martin and its engine is supplied by RTX subsidiary Pratt & Whitney. The stealth fighter currently boasts 19 international customers in addition to the US.
“The latest MSAR report shows the combat-proven F-35 program moving into full-rate production, resuming high-volume development deliveries and growing globally,” Lockheed Martin said in a statement to Breaking Defense. “It also shows that the hard work has shifted from proving the basic aircraft to executing major modernization, improving fleet readiness and controlling long-term sustainment and integration costs.”
Pratt referred an inquiry to the DoD’s F-35 Joint Program Office (JPO).
A spokesperson for the JPO confirmed the rising acquisition cost for the fighter. About $19 billion of the roughly $51 billion acquisition increase can be traced to higher development costs for the aircraft and its engine, the spokesperson said. Another $32 billion stems from greater procurement costs, ranging from more spare parts aimed at boosting lackluster readiness rates to buying an advanced radar. Delays for that radar have forced the Pentagon to accept aircraft without the nose-mounted sensor, Breaking Defense previously reported.
The Pentagon is underway with a slew of enhancements for the F-35. One set of upgrades is meant to enhance the fighter’s engine, while another is meant to deliver a new power and thermal management system to address cooling challenges.
A separate modernization program known as Block 4 — which is over budget and years behind schedule — will add a suite of capabilities for the fighter, officials say. Block 4’s computing backbone, known as Technology Refresh 3, has still not been certified for combat, relegating jets delivered over the past two years to training.
The JPO spokesperson additionally confirmed that the program’s lifecycle costs have fallen beneath $2 trillion. The jet previously surpassed that figure in a 2024 review by the Government Accountability Office.
Lifecycle estimates could change any year with fresh assumptions, or new realities. The most recent MSAR includes data from 2025, which would omit the high tempo of operations for F-35s in the ongoing war against Iran.
Total estimated lifecycle costs are also variable, as Pentagon planners constantly adjust how long the jet will fly; the 2023 MSAR found officials expected the A variant of the aircraft to operate until 2088, but the most recent MSAR projects that F-35A operations will continue until 2083.
“The $2T price tag commonly reported in the media doesn’t come close to telling the whole story,” the recent MSAR says. “The growing global demand speaks for itself. The F-35’s value proposition is unmatched.”
