Canberra organisation Self Help Organisations United Together has announced it will close at the end of May after failing to secure long-term funding.
The more than 35-year-old not-for-profit, which provides administrative and infrastructure support to self-help and support groups, was funded under NDIS transitional arrangements for the past three years but does not have the base funding to operate beyond the middle of year.
The organisation unsuccessfully lobbied the ACT government for a lifeline and announced its intention to close on Thursday.
Two people will lose their jobs.
"The sad outcome for the Canberra community is they lose a hub that has been able to provide low-cost rent, meeting spaces as well as sector co-ordination and that huge amount of knowledge that our two staff will walk away with about the self-help sector in our community," board member Rebecca Davey said.
SHOUT's Pearce headquarters is home to several Canberra groups, including the ACT Down Syndrome Association, Motor Neurone Disease NSW/ACT, Bosom Buddies ACT and Friends of Brain Injured Children.
A number of these groups have indicated they may fold once SHOUT closes.
Canberra and Queanbeyan ADD Support Group secretary Beryl Gover said her organisation had benefited from SHOUT answering its phones, redirecting inquiries, distributing information and providing a photocopier, computer and meeting space.
The group receives less than $10,000 in funding and works with more than 300 people.
She expressed concern for Canberran adults with undiagnosed ADHD who may struggle to find help without someone to call.
"We're going to be lost without them and we could be losing out funding at the end of the year too," Ms Gover said.
"It is such a shame."
Disability Minister Rachel Stephen-Smith said the government was committed to working with community organisations to prepare for the NDIS.
"The ACT Government has been working with SHOUT over a number of years to prepare for the new funding environment of the NDIS," she said.
"This included business development, support and transitional funding, which was recently extended."
Former Chief Minister and SHOUT patron Jon Stanhope called on the ACT government to help the organisation.
"The ACT government, with a budget of $5 billion, can't fund $120,000 to support children with brain injuries, women with breast cancer, children with cancer?" he said.
"The consequences for our community and our society are quite dramatic."
Ms Davey said SHOUT would help its members find new avenues of support.
"If we do not gain funding within the next two weeks we will actively tap into our resource network and attempt to assist our members, especially those who rely on us for accommodation, and try to secure accommodation for them," she said.
"The last thing we want to see is other organisations fail because we can no longer support them."