1.5 Trillion dollars. That is the total program cost of the F-35 Lightning II, the U.S.’ new premiere fighter that will be serving in air forces around the world. It was a program designed to replace the aging fleets of the United States, United Kingdom, Italy, the Netherlands, Australia, and many more. It replaces fighters such as the F/A-18, F-16, and AV-8B. The F-35 is not as expensive as many think, and after breaking down the cost and compared to previous platforms, it is worth the money.
The F-35 is often called the trillion dollar fighter in reference to it's total program cost, which will be approximately $1 trillion dollars. Although this may seem an outrageous number for a plane, it is important to understand that this value is the cost of researching and designing the aircraft, building 2,443 airframes and also paying for fuel consumption, maintenance, spare engines, spare parts, upgrades and expenditure on weapons, from the time the first F-35 flew in 2006 to the time when the F-35 is scheduled to retire all the way in the 2060s. While this level of spending is rarely heard of, this is due to the fact that the United States government nor any of its armed services, has ever predicted the total program cost, including operating and support costs for any other fighter, nor has there ever been an official report, into the total amount that has been spent on previous fighters. All this considered makes the cost of the plane seem much more reasonable, and worth the overall price tag.
According to Loren Thompson, Chief Operating Officer of the Lexington Institute, it would cost 4 trillion then-year dollars to maintain the current aircraft fleet until 2065, rather than replace those fighters with the F-35. It has also been noted that if the US economy maintains it's current growth and average inflation rate of 2%, By 2065, the US economy will generate more than $3 quadrillion, making the total cost of the F-35 program, which represents the majority of the United States' air combat capacity, 0.03 percent of the US economy's total earnings.
 Loren Thompson article: http://www.forbes.com/sites/beltway/2011/06/27/massive-cost-estimate-for-fighter-program-is-misleading/

In terms of individual aircraft cost, the F-35 today in 2019 is currently in LRIP 11 (Low Rate Initial Production 11), where aircraft are bought in small quantities for testing. This practice is enacted to reduce the amount of retrofitting that may have to occur due to design changes during testing, which typically brings reduced efficiency in acquiring and producing materials and components required to manufacture the F-35. Despite this, the most recent LRIP lot of aircraft, LRIP 11, combined with the most recent F135 engine purchase, has resulted in the F-35A currently costing $89 million in US currency. At this current price point, the F-35A is already priced lower than the Dassault Rafale, Eurofighter Typhoon and F-22 Raptor, which are some of the most prominent and advanced fighter aircraft in the world.

$108 million: http://www.defensenews.com/story/defense/air-space/strike/2015/03/25/f35-costs-cracks-development-/70392734/

When the F-35 program completes Initial Operational Test and Evaluation, and Full Rate Production begins in the year 2021, an F-35A will cost less than $85 million US dollars, including the F135 engine and inflation.This is about $ 25 million cheaper than the Rafale and about $40 million cheaper than the Typhoon. In addition, the company that produces the fighter, Lockheed Martin, has previously stated that by 2023, the cost could fall below $80 million.
While the program is over, another misconception is that the F-35 was supposed to cost $ 50 million per plane. While this is partly true, it is often ignored that this was a very early estimate and was to be it's cost in year 2002 dollars, which in 2018 with inflation included is $71 million dollars. In comparison, the F/A-18 Super Hornet currently costs approximately $70.5 million, but provides a significantly shorter range, payload capacity, electronics package and requires other components, such as targeting and electronic warfare pods, to provide a similar baseline to the F-35. All this means is that a fighter that's only a 18% more expensive than an older fighter is much more capable in every respect.
One part of the program that is often blamed for these overruns is concurrency, which involves simultaneous aircraft production and development testing. The purpose behind competition is to advance the point at which an aircraft fleet is sufficiently sized for IOC, while at the same time maturing the production line and allowing a more comprehensive test program with more test flight hours and test points. This enables the F-35 program to proceed as the most complex fighter ever created, but still to be flown safely. The drawback to concurrency is that as problems are found and solved, revised or upgraded aircraft components must be retrofitted to more aircraft. So whereas in a program without concurrency, only half a dozen aircraft would require retrofits, now several dozen require these modifications.
However, while some estimate that these changes result in significant expenditure, it was found that all costs related to competition amounted to approximately $2 billion, which represents approximately 0.5 percent of the F-35's procurement costs, or 0.1 percent of the total cost of the program. All other costs that set the F-35 at a higher price point make the fighter better than its alternatives, making it one of the next generation of fighters
CONCLUSION