Data from the Productivity Commission reveals that, in 2017-18, Tasmania's recidivism rate increased to 46.3 per cent, up from 39.3 per cent five years ago - the fastest increase in the country.

In roughly the same period, the state's prisoner population grew from 451 to 666.

Since April last year, eight prisoners have found public housing upon release and as of last month there were 94 active applications for public housing among prisoners.

The government-funded Reintegration of Ex-Offenders program was axed in 2015, and replaced with Beyond the Wire - a program run and partially-funded by the Salvation Army.

Beyond the Wire manager Don McCrae said it was clear the lack of public housing was harming prisoner reintegration, with housing the crucial first step to accessing drug, alcohol and mental health services they need.

"If people are trying to deal with the complexities of issues they've got, and they're living in a tent or a car, then the chances are they're not going to be benefitting after their release," he said.

"If people are self-medicating with drugs, that leads to dealing or stealing to support their habit.

"I've worked with people who have taken their own lives after being released from prison with nowhere to go."

Mr McCrae works with prisoners to assess their risk factors upon release, and helps them find appropriate housing - but the situation had deteriorated significantly in recent years.

In addition to housing, getting support for drug and alcohol abuse upon release was increasingly tough.

The pharmacotherapy program provides drug-dependent people with methadone, buprenorphine and other drugs to assist them in reducing dependency.

Mr McCrae said the waiting list for pharmacotherapy was a growing issue.

"We're finding significant issues with people getting onto the pharmacotherapy program," he said.

"There's a lot of illicit drug use in prison, so if somebody has got a habit and they're released and want to go straight into this program, they're finding it very hard.

"One person we've worked with said there were 70 people in front of them in the queue."

The Justice Department would not release figures on prisoners serving their full term without parole, but Mr McCrae said more people were choosing to stay in prison due to the difficulties they face upon release, adding to "overcrowding" in Risdon Prison.

The Parole Board of Tasmania has, in the past, highlighted housing issues as a deterrent to people seeking parole, as stable housing was a criteria that must be filled. In its latest report, it believed Beyond the Wire was providing "some relief".

The government disputes that Risdon is overcrowded, as its capacity is 742, but solicitors say this is because bunks are being used in single and double rooms to increase capacity.

Last October, the independent Custodial Inspector Tasmania released a damning report on the conditions in Risdon Prison, including criticism that "mental health services do not meet the needs" of prisoners.

It also described as "unsustainable" the reliance on organisations such as the Salvation Army to partially fund and operate reintegration services.

Ben Bartls, policy officer for Community Legal Centres Tasmania, said it was common for prisoners to comment on the lack of rehabilitation services in prison.

He said recidivism rates in Tasmania were "extremely concerning" and a symptom of a state lacking in public housing with inadequate rehabilitation services.

"The lack of stable and affordable accommodation for persons released from prison makes our community less safe," he said.

"We know that reintegration of ex-prisoners, including a roof over their head is crucial to reducing recidivism.

"Our community is safer when we invest in reintegration, including stable and affordable accommodation for ex-prisoners which in turn assist with family reunification, education, training and employment."

MORE ON PLANS FOR A NORTHERN PRISON:

Prominent Tasmanian rapper Greeley would be the first to admit he had made mistakes in the past, with a fourth assault conviction landing him in jail for two months earlier this year.

In a Facebook post upon his release, he described Risdon Prison as a "holding pen" that was making people "hate the world" and reoffend in the future.

"The system in Tasmania is not equipped to deal with the complex trauma and psychological issues many disadvantaged people face growing up," he wrote.

"It's all spiralling out rapidly and people are dying over drugs and violence."

With the prisoner population rising rapidly, the Tasmanian Government is assessing 10 sites for a $270 million prison in the state's north, along with ongoing works at the Risdon Prison site - projects the government believes will improve reintegration.

Of the 666 prisoners, 398 were involved in programs for domestic abuse, aggression, drug and alcohol abuse and individual support, while 357 had a form of employment in prison.

An additional $16.8 million was provided to the Tasmanian Prison Service to handle cost pressures stemming from the increase in prisoner population, and a home detention scheme - which has 22 offenders - has recently started.

A government spokesperson said the prison service was seeking to improve rehabilitation services, and non-government partnerships would be further developed.

Speaking in Estimates this month, Corrections Minister Elise Archer said the northern prison would drive improvements in Corrective Services.

"[It] will not only relieve pressure on our southern Risdon Prison Complex but will also be designed to create increased opportunities for prisoners to find meaningful work on release and, importantly, provide improved family connections for northern prisoners," she said.

But many in the justice sector are not so sure.

Pat Burton, chief executive of justice reform advocacy group JusTas, said without a shift in focus to preventative measures supporting people at risk of offending and recidivism, Tasmania would be on a dangerous path.

"We're looking at going from more than 600 prisoners at the moment, to upwards of 800, heading towards 900," he said.

"When the prison finally opens in the north, it won't be long before it's full too."