The Australian Greens have agreed to support key measures in Labor's 2026-27 federal budget after securing an eight-week extension to a Senate parliamentary inquiry into the budget's most contested element: $37.8 billion in cuts to the National Disability Insurance Scheme.

The budget, delivered on May 12 by Treasurer Jim Chalmers, contains $63.8 billion in savings over four years. The NDIS reforms account for the largest single component, and include changes that disability advocates say could see up to 300,000 participants lose their current level of support or be redirected to mainstream services that advocacy groups say do not exist at sufficient scale.

The Greens' agreement clears the path for the budget's tax measures, including limits on negative gearing for residential property and a reduction in the capital gains tax discount from 50 per cent to 30 per cent, to pass the Senate.

Greens leader Larissa Waters described the deal as 'a small step in the right direction' and said the eight-week inquiry would give the disability community a formal voice before the reforms were legislated. George Taleporos of Every Australian Counts said communities were 'deeply worried' and feared being pushed toward mainstream services that did not exist at sufficient scale.

'This is the most important and ambitious budget in decades,' Treasurer Jim Chalmers said. 'We are making the investments this country needs while being responsible with the public finances.'

Opposition leader Angus Taylor condemned the arrangement. 'This is a dishonest deal with the Greens that will mean new taxes on housing, savings, investment, small business and younger Australians,' he said.

Former Prime Minister Paul Keating, in a rare public intervention, described the budget as 'structurally sound.' The budget also includes a $53 billion boost to defence spending over ten years and a $14.8 billion fuel resilience package.