The government has saved £4.7bn so far by implementing the recommendations of the Gershon efficiency review, chancellor Gordon Brown announced on Monday.
The review, which was published in July 2004, instructed Whitehall departments to shed more than 84,000 jobs by April 2008 in an attempt to save £20bn.
Delivering his pre-Budget report, Brown said the government has seen the reduction of 18,500 civil service posts, including more than 10,000 from the Department for Work and Pensions and 3,500 from Revenue and Customs.
He also confirmed that the government is on target to complete the relocation of a further 2,000 civil service posts out of London to areas including Cardiff, Derby, Leeds, Edinburgh, Liverpool and Manchester.
In September, it emerged that several departments, including the Home Office, the Foreign & Commonwealth Office and the Department for Education and Skills, had failed to make anyone redundant since mid-2004.