Changes to public sector pensions, announced in last week's Budget, will see hundreds of millions cut from front line public services, according to research from the Liberal Democrats.
The analysis found that while plans to reduce the public service pension scheme discount rate will raise £2bn for the Treasury by 2020, the cost of administering the changes will be passed directly to employers.
The NHS alone will be left with unbudgeted costs of around £650m, while schools will be faced with £426m of costs.
Liberal Democrat leader Tim Farron said: 'David Cameron said he would do whatever it takes to fill the NHS black hole, and we've now discovered that actually means cutting £650m just to help the chancellor's budget-day balance sheet.
'George Osborne cannot pull the wool over people's eyes. Choosing to ask schools, hospitals, and forces to pay £2bn extra in pension contributions has a real cost, and vital services will have to pick up the bill.'