The project - known as Leap 4.5 - will scrutinise almost every area of spending at Britain's luxury car manufacturer, 'The Sunday Times' reported.
The 3-billion-a-year pounds capital budget, focused on research and development and new plants, will be spared.
JLR has one of Britain's biggest success stories since it was bought over by Tata Motors from Ford in 2008 and made 2.6-billion pounds profit last year, has almost 37,000 staff and builds about 500,000 cars a year.
It aims to build one million cars a year by 2020. Sources close to JLR told the newspaper it was a natural time to take stock after such rapid growth and insisted that there were no plans for redundancies.
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Sales in China from July to September were down by a third year-on-year to 20,149 cars, against a wider market fall of 1.9 per cent.
That drop was offset by strong growth in America and Europe. It also faced a 245-million pounds charge on 5,800 vehicles damaged in the huge explosion at the Chinese port of Tianjin in August.
It has largely switched from steel to aluminium bodies, which lead to lower fuel consumption, but tougher emissions rules will require costly upgrades to models.
Leap 4.5 targets 4.5 billion pounds of cumulative savings by the end of the decade.
It is likely to see more models built on similar core skeletons, greater efficiency in manufacturing, supply chains overhauled and recruitment slowed or halted.
The company has repeatedly stressed that it will continue the 3 billion-a-year pounds spending on R&D and new plant and equipment.