The federal government is calling on institutions who are yet to sign up to do so, although it's unknown how many will need to.

There are just under 100 institutions that were named in the royal commission as places where abuse occurred, that have not joined the scheme.

Social Services Minister Paul Fletcher said the 30 groups joining included 22 Anglican institutions, five Baptist organisations, Scouts Queensland, Sisters of Mercy Parramatta, and the Uniting Church in Australia.

"I continue to emphasise the urgency of giving survivors access to redress as soon as they are able," Mr Fletcher said in a statement on Friday.

"The Liberal-National government expects all the institutions where institutional child sexual abuse has occurred to sign up to the national redress scheme as soon as possible."

Applications for redress can only be processed after the relevant institution has joined the scheme, leaving many victims still unable to receive compensation.

The scheme has come under fire from victims' advocates this week, who say it is traumatising survivors and should be overhauled.

Survivors and their supporters will stage a rally in Melbourne on Sunday calling for significant changes to the $3.8 billion scheme.

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Australian Associated Press