Bright children at independent schools are more likely to become high earners than their counterparts in the state sector, a report suggests.
The report advocates 'opening up' private school places
A study for the Sutton Trust charity found 28.6% of pupils whose parents paid full private school fees earned £70,000 or more by their 30s.
For those who attended state schools the proportion was 7.6%.
The study of 296 people also found independent school pupils were more likely to attend leading universities.
Researchers at the London University's Institute of Education followed the group's careers from 1982 to the present day.
They found that, of those who went to private schools with financial help from the government's Assisted Places scheme, 18.2% went on to earn more than £70,000.
The trust is calling for the scheme - set up by the Conservatives in 1980 but abolished by Labour in 1997 - to be reinstated.
The study found that, on average, children on the Assisted Places Scheme gained the equivalent of 8.9 GCSEs at A* to C grade.
For state pupils the figure was 7.7, while for children whose parents paid full independent school fees it was 9.2.
More than a third of assisted place holders went on to an "elite" university, compared with less than one in 10 from state schools.
Sutton Trust chairman Sir Peter Lampl said: "This research shows clearly that there is a very strong case for opening up top independent day schools to talented pupils from non-privileged backgrounds, so that they too can benefit from the academic and social advantages a private education brings."
Professor Geoff Whitty, director of the Institute of Education and co-author of the report, said: "The Assisted Places Scheme clearly benefited many of the individuals who took part in it, but by no means all of them.
"It also took some of the brightest pupils away from the maintained sector.
"State and private schools need to learn from each other and to work more closely together."
Schools Minister Lord Adonis said there would be no return to the Assisted Places Scheme.
He added: "We do not think it right for the government to pay for parents to go private, but rather invest in improving state schools, including academies managed independently within the state system and open to all on a fair basis."
Shadow Education Secretary David Willetts said: "We are not proposing any return to that scheme.
"But we do need to look at ways of breaking down the barriers between private and state education."