Details of a radical shake-up of the state pension are due to be unveiled by the coalition on Monday.
A single flat rate, equivalent to around £144 in today's money, is set to be introduced for new pensioners from 2017 in a bid to simplify the system.
Some six million workers will face higher national insurance payments in future as the practice of "contracting out" the state second pension to employers is ended.
Work and Pensions Secretary Iain Duncan Smith has pushed through the reforms
Those affected are expected to include more than a million private sector staff enrolled in final salary schemes, and an estimated five million public sector workers.
However, it is not clear how many will lose out overall as they are likely to receive a higher state pension than before.
Funds and firms could also alter their schemes and contribution levels to take account of the shift.
Some groups - such as women who have taken career breaks to have children and the self-employed - will be clear winners.
The Department for Work and Pensions confirmed that the White Paper is being published on Monday.
Iain Duncan Smith and his Liberal Democrat deputy at the department, Steve Webb, are believed to have overcome Treasury concerns to get final sign-off for the policy.
Malcolm McLean, a consultant with pensions experts Barnett Waddingham, said: "The concept of a single, simpler-to-understand state pension pitched at a level that lifts as many people as possible off means testing and encourages them to save privately to give themselves a better standard of living in their later years is very desirable if not essential in a society such as ours with an ageing population."
But he warned: "The task of bringing together the various diverse components that currently collectively make up state pension provision was never going to be easy and it is inevitable that there will be some losers as well as winners in the process of change."