(Bloomberg) -- Tens of thousands of Britons who bought homes using Help to Buy could have easily done so without the support of the interest-free government loans, according to the U.K. public spending watchdog.

The government has made around 211,000 loans amounting to 11.7 billion pounds ($15 billion) since the program was introduced in April 2013 in an effort to make home ownership more attainable, the National Audit Office said in a report published Thursday.

But a third of the loans went to buyers who could have purchased a property they wanted without help, and in around 4% of cases household incomes exceeded 100,000 pounds a year.

The findings are likely to fuel criticism that Help to Buy is blunt instrument that has subsidized high earners and boosted the profits of the big house-building firms.

Under Help to Buy, recipients get a 20% loan, with no interest charged for the first five years, allowing them to buy a property with deposit of as little as 5%. In London, where house prices are double the national average, the loans cover up to 40% of the purchase price.

Officials estimate Help to Buy has aided almost 80,000 households who could not have bought a property without the subsidy, though take-up has been low in the least-affordable areas. With the program due to end in 2023, the NAO warned that care will be needed if the government is to meet its target of creating 300,000 homes a year from the mid 2020s.

To contact the reporter on this story: Andrew Atkinson in London at a.atkinson@bloomberg.net

To contact the editors responsible for this story: Fergal O'Brien at fobrien@bloomberg.net, Robert Jameson

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