The new housing subsidies to help first-timer families afford bigger homes will cost the Government at least $150 million annually.
This raises the amount spent on grants for new flats from about $290 million to over $440 million a year, including both the Additional Housing Grant and the Special Housing Grant.
National Development Minister Khaw Boon Wan announced the figures in a Facebook post on Wednesday and added: "The enhancement is not a trivial policy shift, but a significant one made after careful consideration."
Mr Khaw had previously told reporters on Tuesday that "for public housing, we have to...make sure society can afford it. (Policies) cannot be populist and we regret it in a few years time...What we do has to be sustainable for future generations. But as a social policy, we also affirmed in Our Singapore Conversation discussions that home ownership is important."
He added that the Government would do more to help families own homes, but that individuals must also be financially prudent and buy homes they can afford.
On Tuesday, the Special Housing Grant was extended to families and joint singles earning up to $6,500 a month who want to buy new four-room or smaller HDB flats.
Such households can now get up to $20,000 a month. The grant was previously only for families earning up to $2,250 who bought three-room or smaller flats in non-mature estates.