Special account to fund $5b NDIS shortfall

The federal government wants to create a special account to pay for a $5 billion shortfall in national disability insurance scheme funding.

The coalition will pour in budget savings to top up the $6.3 billion in existing disability spending that will be redirected to the NDIS by 2019/20.

Under a bill introduced to parliament on Wednesday, the cash would be earmarked for the NDIS but would sit within the government's consolidated revenue fund.

Social Services Minister Christian Porter accused the previous Labor government of failing to set aside enough money to pay for the scheme.

The special account would provide a sustainable way to meet the funding gap without borrowing, he told parliament.

The coalition will allocate $162 million this financial year to open the account, with more deposits expected as soon as the 2016 budget.

Mr Porter also introduced a bill to expand the board of the scheme's transition body, known as the NDIA, from eight members to 11.

The NDIA is responsible for transitioning from the trial scheme - which involves about 20,000 people - to the full roll out of 460,000 people.

The government argues more board members will be required as the NDIA expands its operations and staff numbers, and wants to appoint a "broader range" of skills and experience.