The Scottish Help to Buy scheme has been extended for an extra two years and will now end in April 2021.
The Scottish government says it will invest an extra £100m in the scheme from April 2019, the original end date.
It says this mean 4,000 new homes will be bought through the scheme and take the total lent through the scheme to £608m.
Scotland launched a Help to Buy scheme in September 2013 and 12,000 households currently benefit from it.
Scottish housing minister Kevin Stewart says: “A third of the annual £50m budget – £18m – will be reserved for sales from SME builders, who were particularly affected by the drop in development finance after the financial crisis.”
The scheme is open to first-time buyers and existing homeowners and provides up to 15 per cent of the purchase price of a new build home. The maximum purchase price is £200,000.
Around two thirds (66 per cent) of Help to Buy (Scotland) households are first-time buyers. Around a third (34 per cent) were existing homeowners.