The Government has insisted its "bonfire of the quangos" is on track to save the taxpayer £2.6 billion.
Cabinet Office minister Francis Maude said that 106 of the more than 900 bodies in existence at the general election have now been axed. Mergers have cut numbers by a further 80.
"The changes we have already made will save £1.4 billion, but by 2015 the Government will save the taxpayer a total of more than £2.6 billion - that's more than £150 per working household," said Mr Maude.
"We have already closed 106 bodies and merged 150 bodies into fewer than 70, but we are only halfway through the first phase of our programme.
"Once we have completed the planned closures and mergers, we will continue to review all remaining quangos to ensure that never again will we end up with so many of these vast bureaucratic and unaccountable bodies."
The influential Commons Public Accounts Committee has previously questioned the £2.6 billion savings estimate, warning it is based on "incomplete and imprecise" information.
The up-front costs of the reorganisation are forecast to be anywhere between £600 million and £900 million.
However, the Cabinet Office insisted the figures had been checked and signed off by top civil servants at departments.
Institute for Government programme director Tom Gash said Mr Maude seemed to be engaged in a "slash and burn" exercise.
"If the figures do stand up to scrutiny and there has been no decrease in government performance in services, this is a good thing but the reliability of the savings claimed is questionable," he said.