Tax breaks for property investors have created a quarter of a trillion dollar budget black hole that could instead fund 500,000 new social homes, a new report has found.

Everybody’s Home, a national campaign to “fix the housing crisis”, is calling on the government to scrap negative gearing and capital gains tax concessions in favour of building more social housing.

It has warned the housing affordability crisis will only worsen if the government doesn’t switch tack from supporting the private market to investing in homes for people being increasingly priced out of the sector.

The latest report proposes a regime of tax reform, finding concessions are on track to cost the budget about $228bn from 2010 to 3203, and that tax breaks for investors have outstripped federal funding on social housing by at least five times.

The report found investment in social housing under Commonwealth-State housing agreements is less today than it was 40 years ago, and that housing policy has been “geared towards subsidising the private market” rather than directly supplying social housing.

The campaign says the cost of those investor tax breaks could build 549,310 social homes over the next decade.

“Taxpayers are being ripped off by property investor write offs. The federal government is spending record amounts on housing to line the pockets of investors. That has made renting and buying homes more expensive than ever,” Everybody’s Home spokesperson Maiy Azize said.

“Tax handouts for investors will be a quarter of a trillion dollar mistake if the government doesn’t change tack. Giving money to investors is a choice. If the government wants to make housing more affordable and fairer for all Australians, it can choose to put money into homes instead of investor profits.

“The government must scrap negative gearing and capital gains tax concessions, and use the revenue savings to build hundreds of thousands of social homes. This would help end Australia’s massive social housing shortfall, and help reach the goal of another one million social homes within the next 20 years.

“Governments must take back responsibility to make housing affordable. It’s time to abolish unfair tax handouts and build the homes we need.”

Negative gearing allows investors to deduct losses incurred on investment properties, such as from interest rates and maintenance, therefore, reducing their overall tax bill.

Under the capital gains tax concessions, tax is levied on only 50 per cent of the capital gain of an asset held for more than one year.

The Greens last year published Parliamentary Budget Office costings that estimated property tax concessions would cost $37.5bn in lost revenue in 2023-24, while capital gains tax discounts were estimated to cost $1.5bn.

The Albanese government’s centrepiece housing policy, the Housing Australia Future Fund, passed in September after months of negotiations with the minor party, with a guaranteed $500m to be spent each year on building new and affordable social homes.

The government last year also announced a separate $2bn Social Housing Accelerator, and increased the Commonwealth Rent Assistance payment in the May budget.

But the Greens want the government to invest even more in social housing, with acting Greens leader Mehreen Faruqi vowing the minor party would keep pushing the government to overhaul the tax concessions.

“These tax breaks are turbo charging the housing crisis, making it easier for wealthy property moguls to buy a property than a first homebuyer, driving up property prices and depriving the government of revenue that could be put to work building housing for those who need it,” she said.

“It is an indictment on Labor’s priorities that they think that $39bn on tax breaks for wealthy property moguls is a reasonable investment, but won’t spend more than $3bn on public housing, as the crisis continues to worsen.”

Prime Minister Anthony Albanese – who famously grew up in social housing – came under fire last year after internal pressure within the Labor Party called for reform on investment property tax concessions.

He dismissed calls to reform the tax concessions, and said he would not revisit the party’s negative gearing policy before the next election, due next year.

“The government’s position is very clear, and it’s a position for which we received a mandate at the 2022 election – and I’m someone who keeps the commitments that we made,” Mr Albanese said last May.

Mr Albanese instead has regularly pointed to the government’s other housing commitments, including building social housing.

Treasurer Jim Chalmers was contacted for comment but did not respond before deadline.