Hundreds of thousands of Australians on the NDIS are being told they will still get support despite reforms to crunch the disability scheme's ballooning costs.
Federal parliament passed changes to the NDIS on Thursday after an agreement with states and territories.
Growth of the NDIS will be capped at eight per cent each year, following concerns the scheme's costs would reach $50 billion a year from 2025/26, higher than the annual cost of Medicare.
Participants will have to go through fresh assessments for funding with stricter budget measures, with the minister able to determine what supports could be provided.
It's estimated $14 billion will be saved in the NDIS over the next four years.
NDIS Minister Bill Shorten said while there may be uncertainty among the 661,000 participants on the scheme, the changes would ensure its sustainability.
"Any talk of change is very anxiety raising with people with disability," he told reporters in Canberra on Thursday.
"What I'm saying to people with disability, what today means for you is you're going to know what you can use your money on.
"You're going to know that you're going to get reasonable and necessary supports, you're going to retain choice and control we're going to have greater accountability in terms of the quality of services people give."
The laws allowed the scheme to get back on track, National Disability Insurance Agency chair Kurt Fearnley said.
"This is an investment in disabled lives," he said.
"We are deeply committed to designing this with people with disabilities."
Mr Shorten admitted communicating how the scheme had changed for participants would be challenging.
"We've got to go full-court press ... now the hard work begins," he said.
The reforms prompted anger among disability advocacy groups, with some saying it left people behind.
People with Disability Australia president Marayke Jonkers said the changes would limit access to supports.
"These reforms will make it harder for people with disability to participate in our schools, workplaces and communities," she said.
"We are concerned people will lose access to support before these new foundational supports are trialled, tested or even designed.
"Our community is deeply worried about what their future looks like."
Greens senator Jordon Steele-John said the laws were a "betrayal" of people with disabilities.
"Labor has ripped the heart out of the NDIS by removing our right to choice and control,'' he said.
Opposition spokesman Michael Sukkar said the changes were sorely needed.
"When we talk about the financial sustainability of a scheme, intertwined with that is the broad public support and acceptance of this huge amount of money," he said.
"Nothing erodes broad public acceptance more than some of the abuse and fraud that we see."
WA Premier Roger Cook said he "reluctantly" agreed to the deal and was concerned the Commonwealth could pass on costs.