Millions of people currently entitled to the state second pension will be worse off as a result of the government’s pension changes, the TUC has claimed.
A TUC report says that anyone with a long working history is likely to lose out, by as much as £2,000 a year.
The second state pension will be abolished when the new single tier pension begins in April 2016.
But the government said the changes will make most people better off.
Around 20 million Britons are currently part of the state second pension scheme, introduced ten years ago to boost pension levels for low earners.
The TUC report suggests that the “vast majority” of them will get less money when they retire.
“Many low and middle-income private sector workers, particularly those several decades away from retirement, could be thousands of pounds a year worse off in retirement,” said Frances O’Grady, the TUC general secretary.
The TUC supports the principle of the single tier pension, but wants it to be raised from the current notional level of £144 a week.
The study claims that anyone on a median income of £26,000 a year, and who has a full employment record, will be worse off as soon as the new pension is introduced.
Such a person retiring in 2030 would receive £1,500 a year less than under the current system.
Someone retiring ten years after that would be £2,000 a year worse off.
Low earners, on an income of £10,000 a year, will be better off if they plan to retire soon after the changes are introduced.
But such people retiring in the 2040’s will be up to £1,700 a year worse off.
However, the government said that most people retiring after 2040 will be better off with the new pension over the course of their retirement.
“The flat rate will provide a fair base, set above the basic level of means test, helping people to know how much they need to save for the kind of retirement they want,” said a spokesman for the Department for Work and Pensions (DWP).
A previous report from the Institute of Fiscal Studies found that people born later than the mid 1980’s will be worse off when the single-tier pension is introduced.
It said that low earners could be £1,000 a year poorer, and high earners could lose £2,300 a year.
But on average, it concluded that women will be around £270 a year better off, and men will be £81 better off.