Purchases through Help to Buy have accounted for just under 6% of all homes bought in the last 15 months, according to new Treasury data.

It shows that the two Help to Buy schemes have been used almost exclusively by first-time buyers to purchase moderately-priced properties.

Altogether, there have been 48,393 completed purchases since Help to Buy launched in April 2013.

Of these, 29,829 were purchased through the equity loan scheme, available on new-builds only which launched last April, and a further 18,564 through the mortgage guarantee scheme which launched last October.

In the second quarter of this year, the number of completions through the Help to Buy mortgage guarantee scheme increased from around 6,300 to 11,200. In May and June, however, completions appeared to have levelled off at around 4,000 a month.

The mortgage guarantee scheme is available to buyers of both new and secondhand homes.

Equity loan purchases, available only on new builds, totalled almost 8,000 in the second quarter

The data shows that 79% of purchases with a mortgage guarantee were completed by first-time buyers (compared to 85% for those buying with an equity loan).

The average price of property bought through Help to Buy mortgage guarantee was £153,148, compared to an average of £259,500 for all home purchases.

The mortgage guarantee scheme is being used most in the north-west, the east, and Scotland, and a lower proportion in London and the south-east.

Help to Buy and wider mortgage market summary, April 2013 – June 2014

Paul Smee, director general of the Council of Mortgage Lenders, said: “It is reassuring to see the data confirming that Help to Buy is essentially delivering its intended objectives.

“The scheme is supporting new housing construction, and is being used extensively by first-time buyers to purchase average-priced properties in all parts of the UK.”