Ninety per cent of the 1.4 million people with a disability in NSW may lose all vital support once the state government's funding of advocacy services ends in two years, disability groups warn.

The NSW government has committed all its disability services spending to the National Disability Insurance Scheme (NDIS), which the federal government is rolling out, and has provided an additional $26 million over two years to state-based advocacy services to assist with the transition to the scheme.

Disability advocates across NSW are urging the Berejiklian government to keep funding disability services. Credit:Esther Han

However, the NSW Disability Advocacy Alliance said the vast majority of people with a disability were ineligible for the NDIS, and it needed ongoing funding at the state level to help them.

"Many people with disability will ... end up incarcerated, homeless or in hospital, putting lives at risk and placing significantly greater stress on the NSW public purse," the alliance's Serena Ovens said.