As many as 61,000 Indian millionaires left the country and settled overseas in the last 14 years, second only to China which saw an exodus of 91,000, according to a report by consultancies New World Wealth and LIO Global.
France, Italy, Russia, Indonesia, South Africa and Egypt round out the top eight, according to the study cited by Time magazine.
The study, released this month, looked at immigration data from 2000 and 2014 indicating applications for a second citizenship or change of domicile (permanent residence).
Britain — its capital city London, in particular — appears to be the most popular destination for the world's rich to settle down in, followed by the US, Singapore, Australia and Hong Kong.
The report said Indians tend to move to countries like Australia and the United Arab Emirates, while Singapore and Hong Kong are popular destinations for China's wealthy.
Despite the large-scale departure of millionaires, India still has the tenth largest number of millionaires at 226 800, while China stands fifth with 608,500. The US tops the list with 4,105,000 millionaires.
Those who leave generally cite reasons like "turmoil in home country, security concerns and optimizing education of children," the report said.
Britain was the top beneficiary of HNWIs from abroad. Most of these HNWIs came from Europe, Russia, China and India.
Inflows into the US predominantly came from China. Notable numbers also came from Britain, India and Russia.
Singapore in second place benefited from a strong migration of HNWIs from China, India and Indonesia.
Australia was boosted by strong inflows from the Asia Pacific region (India, China, Indonesia), as well as Britain and South Africa.
The UAE (mainly Dubai) saw strong inflows from North Africa, India and Middle Eastern countries.
Indian HNWIs tended to move to the UAE, Britain, the US and Australia.