Reaction from the voluntary sector is awaited by the Home Office.
The Home Office is still waiting for charities to respond to the consultation it launched in February to shape the relationship of the National Offender Management Service (Noms) and the voluntary sector.
Noms wants to use the consultation as guidance on how to involve the sector in the running of probation and prison services as it prepares to open a range of new contracts to competition in the coming months.
Charities, including the Probation Boards' Association and Clinks, plan to submit joint responses with other voluntary organisations and said it would take them longer to respond.
"It is vital that voluntary organisations respond to the consultation," said Martin Narey, director of Noms. "What I do not want is for people to wait until the end of next year, once we have already opened competition for contracts, to say it would have been easier if we had done this or that. They need to tell us these things now."
He said that encouraging charities to take on aspects of Noms' work was not an attempt to run public services on the cheap but to improve quality.
"If we wanted to deliver cheap services for offenders who abuse drugs, we would ask our own staff to do it. We are trying to move away from the assumption that the public service knows best."
Crime reduction charity Nacro indicated in a report published last month that it wanted a "seamless resettlement service" that starts at the prison gate and continues after prisoners are released, with resettlement teams in prisons liaising with teams in the community.
Narey confirmed that charities will be offered contracts that include full cost recovery. "We are aware that we need to give certainty to the sector, and we will be able to do that," he said.
Large contracts worth millions of pounds will be offered first, followed by smaller bids that will be more suitable for small charities.
Narey said charities will not be excluded from large contracts because private companies can join up with voluntary organisations whose work adds value to their bids. He also wants to see different charities getting together to offer an attractive package of services, but concedes that they might be reluctant to compromise their independence.
Jo Gordon, head of the voluntary sector unit at Noms, said that a way forward would be to attract larger charities such as the Citizens Advice Bureau, whose main business is not to serve offenders but which has recently developed services in that area.
"Getting more of them involved would open up a range of service providers that are more resourceful than many of the charities specialising in offender support," Gordon said.
The consultation runs until 25 April and will lead to the publication of Noms' strategy report this summer.