F-35’s $1.4 trillion sustainment bill, rising modernization costs and production strain test the limits of global fleet expansion

The F-35 program’s latest acquisition report estimates operating and support costs at $1.395 trillion in then-year dollars through 2083, or $596.36 billion in constant fiscal 2012 dollars. Maintenance alone accounts for about $212.62 billion in constant dollars as more than 1,200 aircraft now operate from 48 bases and 12 ships across 20 nations. Modernization is also expanding: the Technical Refresh 3 completion estimate reached $2.01 billion, while a Block 4 phase is projected at $6.09 billion. Supply shortages, depot capacity and delayed upgrades continue to constrain readiness despite a record 191 deliveries in 2025.