Australians with a disability have condemned a "dirty deal" that will overhaul how NDIS participants use funding and what services they can access.
States and territories have agreed to a deal with the Commonwealth which paves the way for the Albanese government to slow the scheme's growth.
The deal ends a jurisdictional impasse over taming ballooning costs, but advocates said it ignored their demands for beneficiaries to be involved in designing support plans.
The deal to pass the bill was "devastating for people with disability", paralympian and People with Disability Australia president Marayke Jonkers told AAP.
"This has been struck before genuine co-design occurred with those most affected - NDIS participants and the disability community,'' she said.
"Our concerns have not been addressed.
"The legislation, even with amendments, threatens to undermine the scheme and the rights, dignity and access to support for people with disability."
The NDIS supports about half a million Australians, funding and supporting people with a disability to help improve their quality of life.
But the expense of the scheme is ballooning and by 2025/26, it is set to cost the federal budget more than $50 billion per year, higher than Medicare.
To keep the NDIS sustainable, the government wants to cap the scheme's growth at eight per cent per year.
"We're committed to making sure the scheme's here for the future. It's growing at an unsustainable rate," NDIS Minister Bill Shorten told reporters in Canberra on Wednesday.
Federal government legislation includes a reassessment process and tighter budget measures for participants.
It also lets the minister determine what supports are provided under the scheme.
The federal government announced it reached an agreement with the states and territories on Wednesday.
A new approach to dispute resolution and a fast-tracked timeframe for the changes were agreed to get states and territories over the line after concerns delays in the reform would mean there would be service gaps for people with a disability.
The bill will be voted on in the Senate by Thursday, with Mr Shorten hopeful it can clear the lower house on the same day so it can become law before parliament's next sitting in September.
Independent senator Lidia Thorpe called the legislation a "betrayal".
"Bill Shorten has blood on his hands for doing this dirty deal with the coalition," Senator Thorpe said.
"Labor and the coalition have teamed up to characterise NDIS participants as fraudsters, criminals and sexual deviants.
"This gross dehumanisation is Shorten's excuse to cut life-saving services that the whole community should be able to access. Any one of us could end up disabled at any point in our lives."
Greens senator and disability rights advocate Jordon Steele-John called the bill a "betrayal".
"The reality of Labor's bill - which it is ramming through the parliament at the moment - is that it will cause harm, it will make life more difficult and it will lead to the deaths of disabled people," he told reporters in Canberra.
Mr Shorten has also committed to banning access to sex work under the scheme.
Liberal senator Holly Hughes maintains NDIS participants should not be able to hire sex workers under the scheme, but should be given access to sexual assistance.