The savings to companies are of course huge: A new report by Deloitte Touche Tohmatsu , which surveyed 36 global financial institutions in eight countries, estimates that the industry is currently saving more than $9 billion a year from outsourcing – up from $5 billion last year.

India is still the number one spot for offshoring, with around two-thirds of global offshored staff located on the sub-continent. But India risks losing its crown to China.

One third of financial firms now have back-office (mainly IT) processes in China - and with some 200 million Chinese people currently brushing up on their English skills, the country will be able to provide a pool of skilled labor that could compete with India over the next ten years, says Deloitte.

“Offshoring is maturing at a rapid pace but, in the future, the best offshoring strategies will not, and cannot, be based on labor arbitrage alone,” said Chris Gentle, associate partner, financial services at Deloitte and author of the study.

“Financial institutions need to re-engineer business processes or risk simply transferring offshore the legacy inefficiencies of older, onshore processes.”

The offshoring race is currently led by U.K and U.S. banking and capital market institutions. But mainland Europe is catching up.

Meanwhile, Gentle says the companies that fare best are those that outsource around 12 percent of their group headcount, with savings of 55 percent on each business process.

“The companies whose offshoring programs are suffering offshore less than five percent of headcount and typically save 32 percent per process,” he said. “The most efficient offshorers take just 15 months to migrate each process, compared to around 25 months for poorer performers.”