The government is spending over £90m a year on several key online services without being able to demonstrate any clear benefits, according to a report by the National Audit Office (NAO).
The public spending watchdog was looking at two key government sites, Direct.gov.com and Business.gov, and the infrastructure service tool Government Gateway. It said that while they are popular there is no clear benefit being derived.
"It is a good thing that people visited the two main government web sites some 200 million times last year," said the head of the NAO, Amyas Morse.
"However, it's still unclear what benefits have been achieved and at what cost. We cannot conclude, therefore, that the taxpayer is securing value for money."
The report noted that on only one occasion had any savings been identified, with Business.gov saving firms £21 for every £1 spent in the financial year 2010-11, but it added that whether the site was responsible for these savings was unproven.
"It is not possible to say how much of this benefit would have been delivered anyway, if the information had only been available from the multiple web sites from which Business.gov's content is assembled," it said.
The NAO said the Government Digital Service (GDS), the body responsible for maintaining the sites, needs to work harder to ensure its services are measured for clear returns.
"Evaluative mechanisms that can accurately and regularly measure the costs and benefits of transforming public services should be inherent in the GDS's normal operation," it said.
"When working with stakeholders to transfer services to online channels, the GDS should encourage them to develop similarly robust measurement disciplines."
Minister for the Cabinet Office Francis Maude welcomed the NAO report for understanding the work of the GDS is an important part of the government's online strategy.
"The GDS will be the centre for digital government in the UK. It will transform the way people access government information by using digital technology to deliver services that put the user first and give them the smartest and most cost-effective service possible," he said.
"I am therefore delighted the NAO has highlighted the importance of GDS and recognised that the process of transforming government's digital services has been well managed."
The coalition government has set about trying to improve the way IT is administered since taking power by ending expensive contracts, making it easier for SMEs to apply for tenders and taking advantage of new technologies such as the cloud.
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