But what if you could help keep ex-inmates from returning to jail for a fraction of that cost?

A pilot program which helps people in the ACT readjust into the community for a year after they are freed from prison is showing promising results.

Researchers from the University of New South Wales say the ACT's Throughcare program has helped to curb recidivism by 23 per cent.

UNSW Professor of Criminology Eileen Baldry, who was part of the evaluation team, said their findings were "significant".

"Really this is one of the best reductions that we've seen out of a broad programmatic approach to trying to prevent people from going back to prison," Professor Baldry said.

More than 600 people have opted to go through the voluntary program since it was introduced in 2013.

While other states offer prevention and rehabilitation programs targeted at people with complex needs, the ACT is the only jurisdiction to offer it for 12 months without it being part of a supervision order.

Case workers meet the ex-inmates when they are released and give them a care package with food and clothing.

If needed, the case worker will help them attend appointments with Centrelink, the Road Transport Authority or housing and can take them shopping for essential goods.

They also link the former prisoner into drug and alcohol rehabilitation, job groups and other health services.

One participant interviewed by the researchers said ex-inmates used to be released "onto the streets with nowhere to go ... with nothing but a plastic bag".

During the three-year study, about two in five prisoners monitored returned to custody.

However this was a 23 per cent reduction the three years prior to the program taking place.

Researchers also found those who had returned to jail had remained in the community for longer on average.

"It provides a model or an approach which links into all of our mainstream services, housing, health, job skill development and so on," Professor Baldry said.

"That is a very beneficial approach to be taking in because almost everyone who goes into prison comes out again and lives in society and therefore what is best for society is that people become integrated and live fulfilling lives."

The program costs about $4700 per ex-inmate, a cost described as "relatively marginal" compared to the $120,000 spent on keeping them in the AMC.

Corrections minister Shane Rattenbury said the government has spent $4.7 million on the pilot, which is funded until the end of this financial year.

Mr Rattenbury said ongoing funding is being considered as part of the 2017-18 budget process.

"The experiences of clients, and support staff have been encouraging in the program's early stages and the government will consider how support can be improved in the future," Mr Rattenbury said.

Professor Baldry said when you considered the wider cost of recidivism on the Canberra community, the savings for the ACT government stacked up.

"Once you reduce people going back into prison you have a reduction in custodial costs but there's also a reduction in a whole range of other costs, so there are fewer police call-outs, fewer court appearances, there are fewer times that people are in the community are being offended against," she said.

Professor Baldry said up to 85 per cent of people in jail are from the most disadvantaged groups of our community.

"This is a group of people who have high and complex needs on the whole and those are expensive to support, particularly if the only way we address them is when they end up as outpatients in hospital or in crisis mental health unit or picked up by the police and put into custody," she said.

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